Name origin.

For years the volcano's formal name was Alba Patera. "Patera" (pl. "paterae") is Latin for a shallow drinking bowl or saucer. The term was applied to certain ill-defined, scalloped-edged craters that appeared in early spacecraft images to be volcanic (or non-impact) in origin. In September 2007, the International Astronomical Union (IAU) renamed the volcano Alba Mons (Alba Mountain), reserving the term Alba Patera for the volcano's two central depressions (calderas). Nevertheless, the entire volcano is still commonly called Alba Patera in the planetary science literature.  The term Alba is from the Latin word for white and refers to the clouds frequently seen over the region from Earth-based telescopes. The volcano was discovered by the Mariner 9 spacecraft in 1972 and was initially known as the Alba volcanic feature or the Arcadia Ring (in reference to the partial ring of fractures around the volcano). The IAU named the volcano Alba Patera in 1973. The volcano is often simply called Alba when the context is understood.

Location and size.

Alba Mons is centered at in the Arcadia quadrangle (MC-3). Much of the volcano's western flank is located in the adjacent Diacria quadrangle (MC-2). Flows from the volcano can be found as far north as 61°N and as far south as 26°N (in the northern Tharsis quadrangle). If one takes the outer margin of the flows as the volcano's base, then Alba Mons has north–south dimensions of about and a maximum width of. It covers an area of at least 5.7 million km and has a volume of about 2.5 million km. The volcano dominates the northern portion of the Tharsis bulge and is so large and geologically distinct that it can almost be treated as an entire volcanic province unto itself.  Although Alba Mons reaches a maximum elevation of above Mars’ datum, the elevation difference between its summit and surrounding terrain (relief) is much greater on the north side of the volcano (about ) compared to the south side (about ). The reason for this asymmetry is that Alba straddles the dichotomy boundary between the cratered uplands in the south and the lowlands to the north. The plains underlying the volcano slope northward toward the Vastitas Borealis, which has an average surface elevation of "below" datum (-). The southern part of Alba Mons is built on a broad, north-south topographic ridge that corresponds to the fractured, Noachian-aged terrain of Ceraunius Fossae (pictured left).

Physical description.

Alba's size and low profile makes it a difficult structure to study visually, as much of the volcano's relief is indiscernible in orbital photographs. However, between 1997 and 2001, the Mars Orbital Laser Altimeter (MOLA) instrument of the Mars Global Surveyor spacecraft took over 670 million precise elevation measurements across the planet. Using MOLA data, planetary scientists are able to study subtle details of the volcano's shape and topography that were invisible in images from earlier spacecraft such as Viking.  The volcano consists of two, roughly concentric components: 1) an oval-shaped central body with approximate dimensions of by across surrounded by 2) a vast, nearly level apron of lava flows that extends an additional or so outward. The central body is the main topographic edifice of the volcano, marked by pronounced break in slope at the inner boundary of the apron. Extending east and west from the central edifice are two broad fan-shaped lobes (or shoulders), which give the volcano its elongation in the east-west direction. The central edifice has the steepest slopes on the volcano, although they are still only 1°. The crest and upper flanks of the edifice are cut by a partial ring of graben that are part of the Alba and Tantalus Fossae fracture system. Inside the ring of graben is an annulus of very low and in places reversed slopes that forms a plateau on top of which lies a central dome across capped by a nested caldera complex. Thus, the central edifice of Alba Mons resembles a partially collapsed shield volcano with a smaller, summit dome sitting on top (pictured right). The summit dome has a distinct tilt to the east.  The caldera complex consists of a large caldera about by across at the center of the summit dome. A smaller, kidney-shaped caldera (about by ) lies in the southern half of the larger one. Both calderas are relatively shallow, reaching a maximum depth of only.  The larger caldera is bounded at the westernmost end by a steep, semicircular wall tall. This wall disappears at the northern and southern sides of the caldera, where it is buried by volcanic flows originating from the younger, smaller caldera. The smaller caldera is outlined everywhere by a steep wall that varies in height over a range of a few hundred meters. The walls of both calderas are scalloped, suggesting multiple episodes of subsidence and/or mass wasting. Two small shields or domes, several hundred meters high, occur within and adjacent to the large caldera. The shield within the large caldera is about across. It is capped by a peculiar concentric circular feature in diameter (pictured left).  Calderas form by collapse following withdrawal and depletion of a magma chamber after an eruption. Caldera dimensions allow scientists to infer the geometry and depth of the magma chamber beneath the summit of the volcano. The shallowness of Alba's calderas compared to those seen on Olympus Mons and most of the other Tharsis volcanoes implies that Alba's magma reservoir was wider and shallower than those of its neighbors.

Surface characteristics.

Most of the central edifice of Alba Mons is mantled with a layer of dust approximately thick. The dust layer is visible in high resolution images of the summit (pictured right). In places, the dust has been carved into streamlined shapes by the wind and is cut by small landslides. However, some isolated patches of dust appear smooth and undisturbed by the wind.  Heavy dust cover is also indicated by the high albedo (reflectivity) and low thermal inertia of the region. Martian dust is visually bright (albedo > 0.27) and has a low thermal inertia because of its small grain size (<). (See the Martian surface.) However, the thermal inertia is high and albedo lower on the northern flanks of the volcano and in the apron area farther to the north. This suggests that the northern portions of Alba's surface may contain a higher abundance of duricrusts, sand, and rocks compared to the rest of the volcano.  High thermal inertia can also indicate the presence of exposed water ice. Theoretical models of water-equivalent hydrogen (WEH) from epithermal neutrons detected by the Mars Odyssey Neutron Spectrometer (MONS) instrument suggest that the regolith just below the surface on Alba's northern flank may contain 7.6% WEH by mass. This concentration could indicate water present as remnant ice or in hydrated minerals. Alba Mons is one of several areas on the planet that may contain thick deposits of near-surface ice preserved from an earlier epoch (1 to 10 million years ago), when Mars’ axial tilt (obliquity) was higher and mountain glaciers existed at mid-latitudes and tropics. Water ice is unstable at these locations under present conditions and will tend to sublimate into the atmosphere. Theoretical calculations indicate that remnant ice can be preserved below depths of 1 m if it is blanketed by a high-albedo and low-thermal-inertia material, such as dust.  The mineral composition of rocks making up Alba Mons is difficult to determine from orbital reflectance spectrometry because of the predominance of surface dust throughout the region. However, global-scale surface composition can be inferred from the Mars Odyssey gamma-ray spectrometer (GRS). This instrument has allowed scientists to determine the distribution of hydrogen (H), silicon (Si), iron (Fe), chlorine (Cl), thorium (Th) and potassium (K) in the shallow subsurface. Multivariate analysis of GRS data indicates that Alba Mons and the rest of the Tharsis region belongs to a chemically distinct province characterized by relatively low Si (19 wt%), Th (0.58 pppm), and K (0.29 wt%) content, but with Cl abundance (0.56 wt%) higher than Mars' surface average. Low silicon content is indicative of mafic and ultramafic igneous rocks, such as basalt and dunite.  Alba Mons is an unlikely target for unmanned landers in the near future. The thick mantle of dust obscures the underlying bedrock, probably making "in situ" rock samples hard to come by and thus reducing the site's scientific value. The dust layer would also likely cause severe maneuvering problems for rovers. Ironically, the summit region was originally considered a prime backup landing site for the Viking 2 lander because the area appeared so smooth in Mariner 9 images taken in the early 1970s.

Geology.

Much of the geologic work on Alba Mons has focused on the morphology of its lava flows and the geometry of the faults cutting its flanks. Surface features of the volcano, such as gullies and valley networks, have also been extensively studied. These efforts have the overall goal of deciphering the geologic history of the volcano and the volcano-tectonic processes involved in its formation. Such understanding can shed light on the nature and evolution of the Martian interior and the planet's climate history.

Lava flows.

Alba Mons is notable for the remarkable length, diversity, and crisp appearance of its lava flows. Many of the flows radiate from the summit, but others appear to originate from vents and fissures on the lower flanks of the volcano. Individual flows may exceed in length. Lava flows near the summit calderas appear to be significantly shorter and narrower than those on more distal parts of the volcano. The two most common types of volcanic flows on Alba Mons are sheet flows and tube-and-channel fed flows.  Sheet flows (also called tabular flows) form multiple, overlapping lobes with steep margins. The flows typically lack central channels. They are flat-topped and generally about wide on the upper flanks of the volcano but become much wider and lobate toward their downstream (distal) ends. Most appear to originate near the Alba and Tantalus Fossae fracture ring, but the actual vents for the sheet flows are not visible and may have been buried by their own products. Flow thicknesses have been measured for a number of sheet flows based on MOLA data. The flows range from to thick and are generally thickest at their distal margins.  The second major type of lava flows on the flanks of Alba Mons are called tube- and channel-fed flows, or crested flows. They form long, sinuous ridges that radiate outward from the central region of the volcano. They are typically - wide. An individual ridge may have a discontinuous channel or line of pits that run along its crest. Tube- and channel-fed flows are particularly prominent on the western flank of the volcano where individual ridges can be traced for several hundred kilometers. The origin of the ridges is uncertain. They may form by successive buildup of solidified lava at the mouth of a channel or tube, with each pulse of flowing lava adding to the length of the ridge.  In addition to the two main types of flows, numerous undifferentiated flows are present around Alba Mons that are either too degraded to characterize or have hybrid characteristics. Flat-topped ridges with indistinct margins and rugged surfaces, interpreted as lava flows, are common along Alba's lower flanks and become less sharp in appearance with increasing distance from the edifice. In high resolution images, many of the flows on the volcano's upper flanks originally characterized as sheet flows have central channels with levee-like ridges.  The morphology of lava flows can indicate properties of the lava when molten, such as its rheology and flow volume. Together, these properties can provide clues to the lava's composition and eruption rates. For example, lava tubes on Earth only form in lavas of basaltic composition. Silica-rich lavas such as andesite are too viscous for tubes to form. Early quantitative analysis of Alba's lava flows indicated that the lavas had low yield strength and viscosity and were erupted at very high rates. Alba's unusually low profile suggested to some that extremely fluid lavas were involved in the volcano's construction, perhaps komatiites, which are primitive ultramafic lavas that form at very high temperatures. However, more recent work on the tube- and channel-fed flows indicates lava viscosities within the range of typical basalts (between 100 and 1 million Pa s). Calculated flow rates are also lower than originally thought, ranging from 10 to 1.3 million m per second. The lower range of eruption rates for Alba Mons is within the range of the highest terrestrial volcanic flows, such as the 1984 Mauna Loa, North Queensland (McBride Province), and the Columbia River basalts. The highest range is several orders of magnitude higher than the effusive rates for any terrestrial volcano.  Since the late 1980s, some researchers have suspected that Alba Mons eruptions included a significant amount of pyroclastics (and therefore explosive activity) during early phases of its development. The evidence was based on the presence of numerous valley networks on the volcano's northern flanks that appeared to be carved by running water (see below). This evidence combined with thermal inertia data, which indicated a surface dominated by fine-grained materials, suggested an easily erodible material, such as volcanic ash, was present. The volcano's extremely low profile is also more easily explained if the edifice were built largely from pyroclastic flow deposits (ignimbrites).  More recent data from Mars Global Surveyor and the Mars Odyssey spacecraft have shown no specific evidence that explosive eruptions ever occurred at Alba Mons. An alternative explanation for the valley networks on the north side of the volcano is that they were produced through sapping or melting of ice-rich dust deposited during a relatively recent, Amazonian-aged glacial epoch.  In summary, current geologic analysis of Alba Mons suggests that the volcano was built by lavas with rheological properties similar to basalts. If early explosive activity happened at Alba Mons, the evidence (in the form of extensive ash deposits) is largely buried by younger basaltic lavas.

Tectonic Features.

The immense system of fractures surrounding Alba Mons is perhaps the most striking feature of the volcano. The fractures are tectonic features indicating stresses in the planet's lithosphere. They form when the stresses exceed the yield strength of rock, resulting in the deformation of surface materials. Typically, this deformation is manifested as slip on faults that are recognizable in images from orbit.  Alba's tectonic features are almost entirely extensional, consisting of normal faults, graben and tension cracks. The most common extensional features on Alba Mons (and Mars in general) are simple graben. Graben are long, narrow troughs bound by two inward-facing normal faults that enclose a downfaulted block of crust (pictured right). Alba has perhaps the clearest display of simple graben on the entire planet. Alba's graben are up to long, and have a width on the order of –, with depths of –.  Tension cracks (or joints) are extensional features produced when the crust is wrenched apart with no significant slippage between the separated rock masses. In theory they should appear as deep fissures with sharp V-shaped profiles, but in practice they are often difficult to distinguish from graben because their interiors rapidly fill with talus from the surrounding walls to produce relatively flat, graben-like floors. Pit crater chains (catenae), common within many graben on Alba's flanks, may be the surface manifestation of deep tension cracks into which surface material has drained.  The graben and fractures around Alba Mons (hereafter simply called faults unless otherwise indicated) occur in swarms that go by different names depending on their location with respect to Alba's center. South of the volcano is a broad region of intensely fractured terrain called Ceraunius Fossae, which consists of roughly parallel arrays of narrow, north-south oriented faults. These faults diverge around the flanks of the volcano, forming an incomplete ring about in diameter. The set of faults on Alba's western flank is called Alba Fossae and the one on the eastern flank Tantalus Fossae. North of the volcano, the faults splay outward in a northeasterly directions for distances of many hundreds of kilometers. The pattern of faults curving around Alba's flanks has been likened in appearance to the grain of a piece of wood running past a knot. The entire Ceraunius-Alba-Tantalus fault system is at least long and – wide  Several causes for the faults have been suggested, including regional stresses created by the Tharsis bulge, volcanic dikes, and crustal loading by Alba Mons itself. The faults of Ceraunius and Tantalus Fossae are roughly radial to the center of Tharsis and are likely a crustal response to the sagging weight of the Tharsis bulge. The faults ringing Alba's summit region may be due to a combination of loading from the Alba edifice and magma uplift or underplating from the underlying mantle. Some of the fractures are likely the surface expression of gigantic dike swarms radial to Tharsis. An image from High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter (MRO) shows a line of rimless pit craters in Cyane Fossae on the Alba's western flank (pictured right). The pits likely formed by the collapse of surface materials into open fractures created as magma intruded the subsurface rock to form dikes.

Valleys and gullies.

The northern slopes of Alba Mons contain numerous branching channel systems or valley networks that superficially resemble drainage features produced on Earth by rainfall. Alba's valley networks were identified in Mariner 9 and Viking images in the 1970s, and their origin has long been a topic of Mars research. Valley networks are most common in the ancient Noachian-aged southern highlands of Mars, but also occur on the flanks of some of the large volcanoes. The valley networks on Alba Mons are Amazonian in age and thus significantly younger than the majority of those in the southern highlands. This fact presents a problem for researchers who propose that valley networks were carved by rainfall runoff during an early, warm and wet period of Martian history. If the climate conditions changed billions of years ago into today's cold and dry Mars (where rainfall is impossible), how does one explain the younger valleys on Alba Mons? Did Alba's valley networks form differently from those in the highlands, and if so, how? Why do the valleys on Alba Mons occur mainly on the northern flanks of the volcano? These questions are still being debated.  In Viking images, the resemblance of Alba's valley networks to terrestrial pluvial (rainfall) valleys is quite striking. The valley networks show a fine-textured, parallel to dendritic pattern with well-integrated tributary valleys and drainage densities comparable to those on Earth's Hawaiian volcanoes. However, stereoscopic images from the High Resolution Stereo Camera (HRSC) on the European Mars Express orbiter show that the valleys are relatively shallow ( or less) and more closely resemble rills or gullies from intermittent runoff erosion than valleys formed from sustained erosion. It seems likely that the valleys on Alba Mons formed as a result of transient erosional processes, possibly related to snow or ice deposits melting during volcanic activity, or to short-lived periods of global climate change. (See Surface characteristics, above.) Whether the eroded material is an ice-rich dust or friable volcanic ash is still uncertain.

Geologic history.

Alba's well preserved lava flows and faults provide an excellent photogeologic record of the volcano's evolution. Using crater counting and basic principles of stratigraphy, such as superposition and cross-cutting relationships, geologists have been able to reconstruct much of Alba's geologic and tectonic history. Most of the constructional volcanic activity at Alba is believed to have occurred within a relatively brief time interval (about 400 million years) of Mars history, spanning mostly the late Hesperian to very early Amazonian epochs. Faulting and graben formation in the region occurred in two early stages: one preceding and the other contemporaneous with the volcano's formation. Two late stages of graben formation occurred after volcanic activity had largely ended.  Based on Viking Orbiter images, the volcanic materials related to the formation and evolution of the volcano have been grouped into the Alba Patera Formation, which consists of lower, middle, and upper members. Members low in the stratigraphic sequence are older than those lying above, in accordance with Steno's law of superposition.  The oldest unit (lower member) corresponds to the broad lava apron surrounding the Alba Mons edifice. This unit is characterized by sets of low, flat-topped ridges that form a radial pattern extending for hundreds of kilometers to the west, north, and northeast of the main edifice. The ridges are interpreted to be lava flows, although the flow margins are now degraded and difficult to delineate. Broad lava flows with flat-topped ridges are characteristic features of lava flood provinces on Earth (e.g., Columbia River basalt) that were formed at high eruption rates. Thus, the earliest phase of volcanic activity at Alba Mons probably involved massive effusive eruptions of low viscosity lavas that formed the volcano's broad, flat apron. Lava flows of the apron unit straddle the early Hesperian-late Hesperian boundary, having erupted approximately 3700 to 3500 million years ago.  The middle unit, which is early Amazonian in age, makes up the flanks of the main Alba edifice and records a time of more focused effusive activity consisting of long tube- and channel-fed flows. Volcanic spreading occurred in a northward direction forming the two flanking lobes. (See Olympus Mons and Tharsis for a discussion of volcanic spreading on Mars.) Faulting and graben formation at Alba and Tantalus Fossae occurred penecontemporaneous with the lava flows. Any early explosive activity on the volcano may have occurred during the culmination of this middle phase of activity, which ended about 3400 million years ago.  The youngest unit, also early Amazonian, covers the summit plateau, dome, and caldera complex. This period of activity is characterized by relatively short-length sheet flows and construction of the summit dome and the large caldera. This phase ended with an eastward tilting of the summit dome, which may have initiated additional graben formation in Alba Fossae. The last volcanic features to form were the small shield and caldera at the summit. Much later, between about 1,000 and 500 million years ago, a final stage of faulting occurred that may have been related to dike emplacement and the formation of pit crater chains.

Classification.

The classification of the Alba Mons volcano is uncertain. Some workers describe it as a shield volcano, others as a lowland patera (in contrast to highland paterae, which are low-lying ancient volcanoes with furrowed ash deposits located in the southern Martian highlands), and still others consider it a one-of-a-kind volcanic structure unique to Mars. Some researchers have compared Alba Mons to coronae structures on the planet Venus. Alba Mons shares some characteristics with the Syrtis Major volcanic structure. (See Volcanism on Mars.) Both volcanoes are Hesperian in age, cover large areas, have very low relief, and large shallow calderas. Also like Alba, Syrtis Major displays ridged tube- and channel-fed lava flows. Because Alba Mons lies antipodal to the Hellas impact basin, a few researchers have conjectured that the volcano's formation may have been related to crustal weakening from the Hellas impact, which produced strong seismic waves that focused on the opposite side of the planet.

Alba Mons (formerly and still occasionally known as Alba Patera, a term that has since been restricted to the volcano's summit caldera; also initially known as the Arcadia ring) is a volcano located in the northern Tharsis region of the planet Mars. It is the largest volcano on Mars in terms of area, with volcanic flow fields that extend for at least from its summit. Although the volcano has a span comparable to that of the United States, it reaches an elevation of only at its highest point. This is about one-third the height of Olympus Mons, the tallest volcano on the planet. The flanks of Alba Mons have very gentle slopes. The average slope along the volcano's northern (and steepest) flank is 0.5°, which is over five times lower than the slopes on the other large Tharsis volcanoes. In broad profile, Alba Mons resembles a vast but barely raised welt on the planet's surface. It is a unique volcanic structure with no counterpart on Earth or elsewhere on Mars.

Alba Patera je unikátní štítová sopka na povrchu Marsu, která se nachází na severní polokouli v severní oblasti Tharsis, západně od oblasti Tempe Terra, severně od další štítové sopky Ascraeus Mons, severozápadně od sopky Uranius Patera, severovýchodně Abalos Colles, jihozápadně se nachází nejvyšší sopka sluneční soustavy Olympus Mons a na západ pohoří Aceron Fossea. Na severozápadě se pak nachází menší pohoří Arcadia Dorsa.


History.

"Furnus Calcarius" was the Latin name, from the lime kilns used in Roman times. (A Roman bridge still stands in the valley to the south of the town.) Its Provençal name is "Fourcauquié". At the end of the 11th century, a family of the counts of Provence created the county of Forcalquier.  During this time, the town of Forcalquier was the capital of Haute Provence along the Durance, which included the towns of Manosque, Sisteron, Gap and Embrun. Forcalquier minted its own currency, and its church was elevated to the status of a "concathedral".  The counts of Forcalquier grew to a power that could defy the counts of Provence. Rivalry ended in 1195 when Gersende de Sabran, countess of Forcalquier, married Alfonso II, count of Provence. Their son, Ramon Bérenger IV, inherited the two counties.

Population.

The inhabitants are called "Forcalquiérens".

Sights.

Forcalquier is built around the slopes of a steep conical hill, crowned by an octagonal chapel, Notre Dame de Provence, where the medieval citadel once stood. The citadel was destroyed in 1601; the chapel with its panoramic view was built in 1875. It has a carillon that can be heard every Sunday morning during the summer.  The oldest part of the town is the area around the Place Saint-Michel with its Renaissance fountain (1511) and its narrow side-streets. There many doorways dating to the 12th to 16th centuries can be found.  The present commercial and social center of town, the Place du Bourget, is located below the Place St. Michel. The 12th century "concathedral" Notre Dame de l'Assomption with its bell towers stands across from the Place du Bourguet.  The Cordeliers Convent was built in the 13th century by Franciscans named "cordeliers" because of their rope belts. This convent was occupied by monks continuously until the Revolution. It now houses the Université Européenne des Senteurs & Saveurs. The Port de Cordeliers is all that remains of the town's fortified walls.  Monday morning is market day in Forcalquier. The market fills the Place du Bourguet and the adjoining streets.  Noteworthy is the Musée Municipal with its prehistoric and Gallo-Roman artifacts, glass works, and faïence pottery from Mane, Apt and Moustiers-Sainte-Marie.

International relations.

Forcalquier is officially twinned with:

Forcalquier (;, ) is a commune in the Alpes-de-Haute-Provence department in southeastern France. Forcalquier is located between the Lure and Luberon mountain ranges, about south of Sisteron and west of the Durance river. During the Middle Ages it was the capital of Haute-Provence.

Forcalquier je obec na jihu Francie v departementu Alpes-de-Haute-Provence a regionu Provence-Alpes-Côte d'Azur. Má asi 4 600 obyvatel. Nachází se asi 100 km severně od Marseille a nedaleko benediktinského kláštera Ganagobie. Místní hřbitov je na seznamu historického dědictví. Dominantou vsi je osmiboká kaple.


Design and development.

In 1938 Grumman presented a proposal to the U. S. Navy for a twin engine carrier based aircraft, unlike any other fighter aircraft that had ever been considered. The design was for a lightweight fighter (under 10,000 lbs maximum takeoff weight) powered by two 1,200 hp Wright R-1820 engines, with propellers geared to rotate in opposite directions to cancel out the effects of each engine's torque, promising high-speed, and an outstanding rate of climb.  The XF5F Skyrocket was a low-wing monoplane with a short fuselage that began aft of the wing's leading edge with a twin tail assembly that featured a pronounced dihedral to the horizontal stabilizer. The main landing gear and tail wheel were fully retractable.

Operational history.

The aircraft flew for the first time on 1 April 1940. Engine cooling problems arose in the initial flights, resulting in modification to the oil cooling ducts. Further modifications were made to the prototype including reduction in the height of the cockpit canopy, revising the armament installation to four 0.5 in (12.7 mm) machine guns in place of the cannon, redesign of the engine nacelles, adding spinners to the propellers, and extending the fuselage forward of the wing. These changes were completed on 15 July 1941.  Testing by Grumman test pilot "Connie" Converse indicated "the flying qualities for the XF5F-1 were good overall. The counter-rotating props were a nice feature, virtually eliminating the torque effect on takeoff... single-engine performance was good, rudder forces tended to be high in single engine configuration. Spin recovery was positive but elevator forces required for recovery were unusually high. All acrobatics were easily performed, and of course forward visibility was excellent."  In 1941, Navy pilots tested the XF5F-1 in a fly-off against the Supermarine Spitfire, Hawker Hurricane, Curtiss P-40 Warhawk, Bell P-39 Airacobra, Bell XFL Airabonita, Vought XF4U Corsair, Grumman F4F Wildcat, and Brewster F2A Buffalo. LCDR Crommelin, in charge of the test, stated in a 1985 letter to George Skurla, Grumman president:"for instance, I remember testing the XF5F against the XF4U on climb to the 10,000 foot level. I pulled away from the Corsair so fast I thought he was having engine trouble. The F5F was a carrier pilot's dream, as opposite rotating propellers eliminated all torque and you had no large engine up front to look around to see the LSO (landing signal officer)... The analysis of all the data definitely favored the F5F, and the Spitfire came in a distant second.... ADM Towers told me that securing spare parts... and other particulars which compounded the difficulty of building the twin-engine fighter, had ruled out the Skyrocket and that the Bureau had settled on the Wildcat for mass production."Additional changes were needed after further flight tests that were not completed until 15 January 1942. In the meantime, Grumman began work on a more advanced twin-engine shipboard fighter, the XF7F-1, and further testing with the XF5F-1 supported the development of the newer design. The prototype continued to be used in various tests, although plagued by various landing gear problems, until it was struck from the list of active aircraft after it made a belly landing on 11 December 1944.

Notable appearances in media.

The XF5F Skyrocket was the only propeller fighter aircraft flown by the "Blackhawk"s in Quality Comics monthly title "Military Comics", which ran throughout World War II. The XF5F remained the "Blackhawk" Squadron's mount until their conversion to jet aircraft in Quality's retitled "Modern Comics" at the start of the jet age.

The Grumman XF5F Skyrocket was a prototype twin-engined shipboard fighter interceptor. The United States Navy ordered one prototype, model number G-34, from Grumman Aircraft Engineering Corporation on 30 June 1938; its designation was XF5F-1. The aircraft had a unique appearance: The forward "nose" of the fuselage did not extend forward of the wing. Provisions were included for two 20 mm (0.906 in) Madsen cannon as armament.

Grumman XF5F Skyrocket byl prototyp dvoumotorového palubního stíhacího letounu. V době jeho vzniku začaly ve službě na letadlových lodích jednoplošné letouny vytlačovat dvouplošníky a proto byla jeho koncepce poměrně odvážná. Existovala také pozemní varianta tohoto typu, označená Grumman XP-50.


Career.

Khrushchev held several advanced engineering degrees. From the Ukrainian Academy of Science, he earned his doctoral degree, and he earned a Ph.D. from the Moscow Technical University. In addition, he earned an M.A. degree with distinction from the Moscow Electric Power Institute. He also held an "occasional" professorship at the Naval War College in Newport, Rhode Island, meaning he was not a full-time professor (though he was for some time), but did teach there fairly often.  Prior to emigrating from the Soviet Union to the United States in 1991, Khrushchev worked in various high-level engineering positions. From 1968 to 1991, he served at the Control Computer Institute in Moscow, where he rose from section head to first deputy director in charge of research. From the years 1958 to 1968, Dr. Khrushchev worked as an engineer, then later as a deputy section head in charge of guidance systems for missile and space design. In this capacity, he worked on cruise missiles for submarine craft, military and research spacecraft, moon vehicles, and the "Proton" space booster.  He often spoke to American audiences to share his memories of the "other" side of the Cold War. Khrushchev served as an advisor to the Cold War Museum. He was a Senior Fellow at the Watson Institute for International and Public Affairs at Brown University.

Personal life.

On July 12, 1999, Khrushchev and his wife, Valentina, became naturalized citizens of the United States. His son from a previous marriage, Nikita Sergeyevich Khrushchev, a Russian journalist, died on February 22, 2007, aged 47, from a stroke. He had another son, whose name is also Sergei.  Khrushchev died on June 18, 2020 in Cranston, Rhode Island; a cause of death was not initially reported.

Sergei Nikitich Khrushchev (, July 2, 1935 – June 18, 2020) was a Russian engineer and the son of former Soviet Premier Nikita Khrushchev and his wife Nina Petrovna Khrushcheva. He moved to the United States in 1991 and was a naturalized American citizen.

Sergej Nikitič Chruščov (rusky "Серге́й Ники́тич Хрущёв"; 2. července 1935 Moskva – 18. června 2020 Cranston, Rhode Island) byl syn sovětského vůdce Nikity Chruščova.


Background.

The possibility of a Jewish homeland in Palestine had been a goal of Zionist organizations since the late 19th century. In 1917 British Foreign Secretary Arthur Balfour stated in a letter to British Jewish community leader Walter, Lord Rothschild that:  His Majesty's government view with favour the establishment in Palestine of a national home for the Jewish people, and will use their best endeavours to facilitate the achievement of this object, it being clearly understood that nothing shall be done which may prejudice the civil and religious rights of existing non-Jewish communities in Palestine, or the rights and political status enjoyed by Jews in any other country.  Through this letter, which became known as the Balfour Declaration, British government policy officially endorsed Zionism. After World War I, the United Kingdom was given a mandate for Palestine, which it had conquered from the Ottomans during the war. In 1937 the Peel Commission suggested partitioning Mandate Palestine into an Arab state and a Jewish state, though the proposal was rejected as unworkable by the government and was at least partially to blame for the renewal of the 1936–39 Arab revolt. In the face of increasing violence after World War II, the British handed the issue over to the recently established United Nations. The result was Resolution 181(II), a plan to partition Palestine into "Independent Arab and Jewish States and the Special International Regime for the City of Jerusalem". The Jewish state was to receive around 56% of the land area of Mandate Palestine, encompassing 82% of the Jewish population, though it would be separated from Jerusalem. The plan was accepted by most of the Jewish population, but rejected by much of the Arab populace. On 29 November 1947, the resolution to recommend "to the United Kingdom, as the mandatory Power for Palestine, and to all other Members of the United Nations the adoption and implementation, with regard to the future government of Palestine, of the Plan of Partition with Economic Union" was put to a vote in the United Nations General Assembly. The result was 33 to 13 in favour of the resolution, with 10 abstentions. Resolution 181(II): "PART I: Future constitution and government of Palestine: A. TERMINATION OF MANDATE, PARTITION AND INDEPENDENCE: Clause 3" provides:Independent Arab and Jewish States and the Special International Regime for the City of Jerusalem,... shall come into existence in Palestine two months after the evacuation of the armed forces of the mandatory Power has been completed but in any case not later than 1 October 1948.  The Arab countries (all of which had opposed the plan) proposed to query the International Court of Justice on the competence of the General Assembly to partition a country, but the resolution was rejected.

Drafting the text.

The first draft of the declaration was made by Zvi Berenson, the legal advisor of the Histadrut trade union and later a Justice of the Supreme Court, at the request of Pinchas Rosen. A revised second draft was made by three lawyers, A. Beham, A. Hintzheimer and Z.E. Baker, and was framed by a committee including David Remez, Pinchas Rosen, Haim-Moshe Shapira, Moshe Sharett and Aharon Zisling. A second committee meeting, which included David Ben-Gurion, Yehuda Leib Maimon, Sharett and Zisling produced the final text.

Minhelet HaAm Vote.

On 12 May 1948, the Minhelet HaAm (, lit. "People's Administration") was convened to vote on declaring independence. Three of the thirteen members were missing, with Yehuda Leib Maimon and Yitzhak Gruenbaum being blocked in besieged Jerusalem, while Yitzhak-Meir Levin was in the United States.  The meeting started at 13:45 and ended after midnight. The decision was between accepting the American proposal for a truce, or declaring independence. The latter option was put to a vote, with six of the ten members present supporting it:  Chaim Weizmann, the Chairman of the World Zionist Organization, and soon to be first President of Israel, endorsed the decision, after reportedly asking "What are they waiting for, the idiots?"

Final wording.

The draft text was submitted for approval to a meeting of Moetzet HaAm at the JNF building in Tel Aviv on 14 May. The meeting started at 13:50 and ended at 15:00, an hour before the declaration was due to be made. Despite ongoing disagreements, members of the Council unanimously voted in favour of the final text. During the process, there were two major debates, centring on the issues of borders and religion.

Borders.

The borders were not specified in the Declaration, although its 14th paragraph indicated a willingness to cooperate in the implementation of the UN Partition Plan. The original draft had declared that the borders would be decided by the UN partition plan. While this was supported by Rosen and Bechor-Shalom Sheetrit, it was opposed by Ben-Gurion and Zisling, with Ben-Gurion stating, "We accepted the UN Resolution, but the Arabs did not. They are preparing to make war on us. If we defeat them and capture western Galilee or territory on both sides of the road to Jerusalem, these areas will become part of the state. Why should we obligate ourselves to accept boundaries that in any case the Arabs don't accept?" The inclusion of the designation of borders in the text was dropped after the provisional government of Israel, the Minhelet HaAm, voted 5–4 against it. The Revisionists, committed to a Jewish state on both sides of the Jordan River (that is, including Transjordan), wanted the phrase "within its historic borders" included, but were unsuccessful.

Religion.

The second major issue was over the inclusion of God in the last section of the document, with the draft using the phrase "and placing our trust in the Almighty". The two rabbis, Shapira and Yehuda Leib Maimon, argued for its inclusion, saying that it could not be omitted, with Shapira supporting the wording "God of Israel" or "the Almighty and Redeemer of Israel". It was strongly opposed by Zisling, a member of the secularist Mapam. In the end the phrase "Rock of Israel" was used, which could be interpreted as either referring to God, or the land of Eretz Israel, Ben-Gurion saying "Each of us, in his own way, believes in the 'Rock of Israel' as he conceives it. I should like to make one request: Don't let me put this phrase to a vote." Although its use was still opposed by Zisling, the phrase was accepted without a vote.

Name.

The writers also had to decide on the name for the new state. Eretz Israel, Ever (from the name Eber), Judea, and Zion were all suggested, as were Ziona, Ivriya and Herzliya. Judea and Zion were rejected because, according to the partition plan, Jerusalem (Zion) and most of the Judean mountains would be outside the new state. Ben-Gurion put forward "Israel" and it passed by a vote of 6–3. Official documents released in April 2013 by the State Archive of Israel show that days before the establishment of the State of Israel in May 1948, officials were still debating about what the new country would be called in Arabic: Palestine (فلسطين Filastin), Zion (صهيون Sayoun) or Israel (إسرائيل Eesra’il). Two assumptions were made: "That an Arab state was about to be established alongside the Jewish one in keeping with the UN’s partition resolution the year before, and that the Jewish state would include a large Arab minority whose feelings needed to be taken into account". In the end, the officials rejected the name Palestine because they thought that would be the name of the new Arab state and could cause confusion so they opted for the most straightforward option of Israel.

Other items.

At the meeting on 14 May, several other members of Moetzet HaAm suggested additions to the document. Meir Vilner wanted it to denounce the British Mandate and military but Sharett said it was out of place. Meir Argov pushed to mention the Displaced Persons camps in Europe and to guarantee freedom of language. Ben-Gurion agreed with the latter but noted that Hebrew should be the main language of the state.  The debate over wording did not end completely even after the Declaration had been made. Declaration signer Meir David Loewenstein later claimed, "It ignored our sole right to Eretz Israel, which is based on the covenant of the Lord with Abraham, our father, and repeated promises in the Tanach. It ignored the aliya of the Ramban and the students of the Vilna Gaon and the Ba'al Shem Tov, and the [rights of] Jews who lived in the 'Old Yishuv'."

Declaration ceremony.

The ceremony was held in the Tel Aviv Museum (today known as Independence Hall) but was not widely publicised as it was feared that the British Authorities might attempt to prevent it or that the Arab armies might invade earlier than expected. An invitation was sent out by messenger on the morning of 14 May telling recipients to arrive at 15:30 and to keep the event a secret. The event started at 16:00 (a time chosen so as not to breach the sabbath) and was broadcast live as the first transmission of the new radio station Kol Yisrael.  The final draft of the declaration was typed at the Jewish National Fund building following its approval earlier in the day. Ze'ev Sherf, who stayed at the building in order to deliver the text, had forgotten to arrange transport for himself. Ultimately, he had to flag down a passing car and ask the driver (who was driving a borrowed car without a license) to take him to the ceremony. Sherf's request was initially refused but he managed to persuade the driver to take him. The car was stopped by a policeman for speeding while driving across the city though a ticket was not issued after it was explained that he was delaying the declaration of independence. Sherf arrived at the museum at 15:59.  At 16:00, Ben-Gurion opened the ceremony by banging his gavel on the table, prompting a spontaneous rendition of Hatikvah, soon to be Israel's national anthem, from the 250 guests. On the wall behind the podium hung a picture of Theodor Herzl, the founder of modern Zionism, and two flags, later to become the official flag of Israel.  After telling the audience "I shall now read to you the scroll of the Establishment of the State, which has passed its first reading by the National Council", Ben-Gurion proceeded to read out the declaration, taking 16 minutes, ending with the words "Let us accept the Foundation Scroll of the Jewish State by rising" and calling on Rabbi Fishman to recite the Shehecheyanu blessing.

Signatories.

As leader of the Yishuv, David Ben-Gurion was the first person to sign. The declaration was due to be signed by all 37 members of Moetzet HaAm. However, twelve members could not attend, with eleven of them trapped in besieged Jerusalem and one abroad. The remaining 25 signatories present were called up in alphabetical order to sign, leaving spaces for those absent. Although a space was left for him between the signatures of Eliyahu Dobkin and Meir Vilner, Zerach Warhaftig signed at the top of the next column, leading to speculation that Vilner's name had been left alone to isolate him, or to stress that even a communist had agreed with the declaration. However, Warhaftig later denied this, stating that a space had been left for him (as he was one of the signatories trapped in Jerusalem) where a Hebraicised form of his name would have fitted alphabetically, but he insisted on signing under his actual name so as to honour his father's memory and so moved down two spaces. He and Vilner would be the last surviving signatories, and remained close for the rest of their lives. Of the signatories, two were women (Golda Meir and Rachel Cohen-Kagan).  When Herzl Rosenblum, a journalist, was called up to sign, Ben-Gurion instructed him to sign under the name Herzl Vardi, his pen name, as he wanted more Hebrew names on the document. Although Rosenblum acquiesced to Ben-Gurion's request and legally changed his name to Vardi, he later admitted to regretting not signing as Rosenblum. Several other signatories later Hebraised their names, including Meir Argov (Grabovsky), Peretz Bernstein (then Fritz Bernstein), Avraham Granot (Granovsky), Avraham Nissan (Katznelson), Moshe Kol (Kolodny), Yehuda Leib Maimon (Fishman), Golda Meir (Meyerson/Myerson), Pinchas Rosen (Felix Rosenblueth) and Moshe Sharett (Shertok). Other signatories added their own touches, including Saadia Kobashi who added the phrase "HaLevy", referring to the tribe of Levi.  After Sharett, the last of the signatories, had put his name to paper, the audience again stood and the Israel Philharmonic Orchestra played "Hatikvah". Ben-Gurion concluded the event with the words "The State of Israel is established! This meeting is adjourned!"

Aftermath.

The declaration was signed in the context of civil war between the Arab and Jewish populations of the Mandate that had started the day after the partition vote at the UN six months earlier. Neighbouring Arab states and the Arab League were opposed to the vote and had declared they would intervene to prevent its implementation. In a on 15 May 1948 to the Secretary-General of the United Nations, the Secretary-General of the League of Arab States claimed that "the Arab states find themselves compelled to intervene in order to restore law and order and to check further bloodshed".  Over the next few days after the declaration, armies of Egypt, Trans-Jordan, Iraq, and Syria engaged Israeli troops inside the area of what had just ceased to be Mandatory Palestine, thereby starting the 1948 Arab–Israeli War. A truce began on 11 June, but fighting resumed on 8 July and stopped again on 18 July, before restarting in mid-October and finally ending on 24 July 1949 with the signing of the armistice agreement with Syria. By then Israel had retained its independence and increased its land area by almost 50% compared to the 1947 UN Partition Plan.  Following the declaration, Moetzet HaAm became the Provisional State Council, which acted as the legislative body for the new state until the first elections in January 1949.  Many of the signatories would play a prominent role in Israeli politics following independence; Moshe Sharett and Golda Meir both served as Prime Minister, Yitzhak Ben-Zvi became the country's second president in 1952, and several others served as ministers. David Remez was the first signatory to pass away, dying in May 1951, while Meir Vilner, the youngest signatory at just 29, was the longest living, serving in the Knesset until 1990 and dying in June 2003. Eliyahu Berligne, the oldest signatory at 82, died in 1959.  Eleven minutes after midnight, the United States "de facto" recognized the State of Israel. This was followed by Shah Mohammad Reza Pahlavi's Iran (which had voted against the UN partition plan), Guatemala, Iceland, Nicaragua]l, Romania, and Uruguay. The Soviet Union was the first nation to fully recognize Israel de jure on 17 May 1948, followed by Poland, Czechoslovakia, Yugoslavia, Ireland, and South Africa. The United States extended official recognition after the first Israeli election, as Truman had promised on 31 January 1949. By virtue of General Assembly Resolution 273 (III), Israel was admitted to membership in the United Nations on 11 May 1949.  In the three years following the 1948 Palestine war, about 700,000 Jews immigrated to Israel, residing mainly along the borders and in former Arab lands. Around 136,000 were some of the 250,000 displaced Jews of World War II. And from the 1948 Arab–Israeli War until the early 1970s, 800,000–1,000,000 Jews left, fled, or were expelled from their homes in Arab countries; 260,000 of them reached Israel between 1948 and 1951; and 600,000 by 1972.  At the same time, a large number of Arabs left, fled or were expelled from, what became Israel. In the "Report of the Technical Committee on Refugees (Submitted to the United Nations Conciliation Commission for Palestine in Lausanne on 7 September 1949) – (A/1367/Rev.1)", in paragraph 15, the estimate of the statistical expert, which the Committee believed to be as accurate as circumstances permitted, indicated that the number of refugees from Israel-controlled territory amounted to approximately 711,000.

Status in Israeli law.

Paragraph 13 of the Declaration provides that the State of Israel would "be based on freedom, justice and peace as envisaged by the prophets of Israel; it will ensure complete equality of social and political rights to all its inhabitants irrespective of religion, race or sex;". However, the Knesset maintains that the declaration is neither a law nor an ordinary legal document. The Supreme Court has ruled that the guarantees were merely guiding principles, and that the declaration is not a constitutional law making a practical ruling on the upholding or nullification of various ordinances and statutes.  In 1994 the Knesset amended two basic laws, and Freedom of Occupation, introducing (among other changes) a statement saying "the fundamental human rights in Israel will be honored (...) in the spirit of the principles included in the declaration of the establishment of the State of Israel."

The scroll.

Although Ben-Gurion had told the audience that he was reading from the scroll of independence, he was actually reading from handwritten notes because only the bottom part of the scroll had been finished by artist and calligrapher Otte Wallish by the time of the declaration (he did not complete the entire document until June). The scroll, which is bound together in three parts, is generally kept in the country's National Archives.

The Israeli Declaration of Independence, formally the Declaration of the Establishment of the State of Israel (), was proclaimed on 14 May 1948 (5 Iyar 5708) by David Ben-Gurion, the Executive Head of the World Zionist Organization, Chairman of the Jewish Agency for Palestine, and soon to be first Prime Minister of Israel. It declared the establishment of a Jewish state in Eretz-Israel, to be known as the State of Israel, which would come into effect on termination of the British Mandate at midnight that day. The event is celebrated annually in Israel with a national holiday Independence Day on 5 Iyar of every year according to the Hebrew calendar.

Deklarace nezávislosti (:, Hachrazat ha-acma'ut) Izraele je oficiální oznámení, že nový židovský stát, nazvaný Stát Izrael (), byl formálně založen v části oblasti dříve známé jako Britský mandát Palestina, v místech, kde se dříve nacházelo království Izraelské, Judské a Judea. Stát Izrael byl vyhlášen pouze na oblastech přidělených mu plánem OSN na rozdělení Palestiny (území Izraele se později zvětší jako důsledek války za nezávislost v roce 1948).


Design and development.

A United States Army Air Corps (USAAC) specification based upon a Curtiss proposal was the basis for an order placed in September 1939 for the XP-46. The requirements called for a single-engine, low-wing aircraft, slightly smaller than the P-40, and with a wide-track, inward-retracting landing gear. The selected powerplant was a 1,150 hp (858 kW) Allison V-1710-39 V-12 engine. The planned armament included two.50 in (12.7 mm) synchronized machine guns in the forward fuselage and provisions for eight.30 in (7.62 mm) wing-mounted guns. The USAAC later added requirements for self-sealing fuel tanks and 65 lb (29 kg) of armor, the weights of which were to adversely affect performance.

Testing.

In 1940 the British Purchasing Commission placed an order for the P-46 as a replacement for the P-40, the name 'Kittyhawk' being allocated by the Air Ministry in anticipation of receiving the aircraft.  However, the USAAC asked Curtiss in July 1940 – while the XP-46 prototypes were under construction – to prioritize an upgraded P-40, featuring the engine intended for the XP-46. This would also avoid disruptions to the production line caused by any switch to a new airframe. The British order for the P-46 was later cancelled, and the 'Kittyhawk' name subsequently applied to the upgraded P-40.  Two prototypes, designated XP-46A, were nevertheless delivered to the USAAC; the first flight occurred on 15 February 1941. The type's performance during trials was found to be inferior to the then-contemporary P-40D. As the P-46 offered no significant improvement on the P-40, the program was cancelled.  A myth claims that work on the XP-46 was the basis of the North American NA-73X – the prototype P-51 Mustang. While North American Aviation (NAA) purchased technical aerodynamic data on the P-40 and XP-46 from Curtiss for $56,000, and there are certain design similarities in the radiator/oil-cooler configuration of the two types, North American had already made significant progress on its design.

The Curtiss XP-46 was a 1940s United States prototype fighter aircraft. It was a development of the Curtiss-Wright Corporation in an effort to introduce the best features found in European fighter aircraft in 1939 into a fighter aircraft which could succeed the Curtiss P-40, then in production.

Curtiss XP-46 (Curtiss Model 86) byl prototyp amerického jednomístného jednomotorového stíhacího dolnoplošníku z období druhé světové války. Byl to pokus továrny Curtiss-Wright Corporation o vývoj perspektivní náhrady typu Curtiss P-40 (tovární označení Model 81-A; prototyp byl zalétáván od října 1938, přičemž v té době byl stále ještě zdokonalován a upravován — řada částí konstrukce byla přestavována; první sériový stroj s/n 39-156 byl dodán teprve v dubnu 1940).


Etymology and history.

The stone's name derives (via,, and Middle English "melochites") from Greek Μολοχίτης λίθος "molochites lithos", "mallow-green stone", from μολόχη "molochē", variant of μαλάχη "malāchē", "mallow". The mineral was given this name due to its resemblance to the leaves of the mallow plant.  Malachite was extensively mined at the Great Orme Mines in Britain 3,800 years ago, using stone and bone tools. Archaeological evidence indicates that mining activity ended, with up to 1,760 tonnes of copper being produced from the mined Malachite.  Archaeological evidence indicates that the mineral has been mined and smelted to obtain copper at Timna Valley in Israel for more than 3,000 years. Since then, malachite has been used as both an ornamental stone and as a gemstone.

Occurrence.

Malachite often results from the weathering of copper ores, and is often found with azurite (Cu(CO)(OH)), goethite, and calcite. Except for its vibrant green color, the properties of malachite are similar to those of azurite and aggregates of the two minerals occur frequently. Malachite is more common than azurite and is typically associated with copper deposits around limestones, the source of the carbonate.  Large quantities of malachite have been mined in the Urals, Russia. Ural malachite is not being mined at present, but G.N Vertushkova reports the possible discovery of new deposits of malachite in the Urals. It is found worldwide including in the Democratic Republic of the Congo; Gabon; Zambia; Tsumeb, Namibia; Mexico; Broken Hill, New South Wales; Lyon, France; Timna Valley, Israel; and the Southwestern United States, most notably in Arizona.

Use.

Malachite was used as a mineral pigment in green paints from antiquity until 1800. The pigment is moderately lightfast, sensitive to acids, and varying in color. This natural form of green pigment has been replaced by its synthetic form, verditer, among other synthetic greens.  Malachite is also used for decorative purposes, such as in the Malachite Room in the Hermitage Museum, which features a huge malachite vase, and the Malachite Room in Castillo de Chapultepec in Mexico City. "The Tazza", a large malachite vase, one of the largest pieces of malachite in North America and a gift from Tsar Nicholas II, stands as the focal point in the centre of the room of Linda Hall Library.

Symbolism and superstitions.

A 17th-century Spanish superstition held that having a child wear a lozenge of malachite would help them sleep, and keep evil spirits at bay. Marbodus recommended malachite as a talisman for young people because of its protective qualities and its ability to help with sleep. It has also historically been worn for protection from lightning and contagious diseases and for health, success, and constancy in the affections. During the Middle Ages it was customary to wear it engraved with a figure or symbol of the Sun to maintain health and to avert depression to which Capricorns were considered vulnerable.  In ancient Egypt the colour green (wadj) was associated with death and the power of resurrection as well as new life and fertility. Ancient Egyptians believed that the afterlife contained an eternal paradise, referred to as the "Field of Malachite", which resembled their lives but with no pain or suffering.

Malachite is a copper carbonate hydroxide mineral, with the formula CuCO (OH). This opaque, green-banded mineral crystallizes in the monoclinic crystal system, and most often forms botryoidal, fibrous, or stalagmitic masses, in fractures and deep, underground spaces, where the water table and hydrothermal fluids provide the means for chemical precipitation. Individual crystals are rare, but occur as slender to acicular prisms. Pseudomorphs after more tabular or blocky azurite crystals also occur.

Malachit je uhličitan mědi s OH skupinou. Malachit má zpravidla zelenou barvu, která se může pohybovat v odstínech od světle zelené až po černozelenou. Je neprůhledný. Nejčastěji se vyskytuje v podobě práškovitých, zemitých, vrstevnatých, ledvinitých a krápníkovitých agregátů. Příležitostně také ve formě malých sloupcovitých a jehlicovitých krystalů. Jeho výskyt je vázán na oblasti výskytů sulfidů mědi, např. chalkopyrit, jejichž přeměnou vzniká.


History.

Rinzai is the Japanese line of the Chinese Linji school, which was founded during the Tang dynasty by Linji Yixuan (Japanese: Rinzai Gigen).

Kamakura period (1185–1333).

Though there were several attempts to establish Rinzai lines in Japan, it first took root in a lasting way through the efforts of the monk Myōan Eisai. In 1168, Myōan Eisai traveled to China, whereafter he studied Tendai for twenty years. In 1187, he went to China again, and returned to establish a Linji lineage, which is known in Japan as Rinzai. Decades later, (1235–1308) also studied Linji teachings in China before founding the Japanese Ōtōkan lineage, the most influential and only surviving branch of Rinzai.  The time during which Rinzai Zen was established in Japan also saw the rise of the samurai to power. Along with early imperial support, Rinzai came to enjoy the patronage of this newly ascendant warrior class.

Muromachi (or Ashikaga) period (1336–1573).

During the Muromachi period, the Rinzai school was the most successful of the schools because it was favoured by the "shōgun". The school may be said to have truly flowered and achieved a distinctly Japanese identity with Shūhō Myōchō (aka Daitō Kokushi 1283–1337) and Musō Soseki (1275–1351), two influential Japanese Zen masters who did not travel to China to study.

Five Mountain System.

In the beginning of the Muromachi period, the system was fully worked out. The final version contained five temples of both Kyoto and Kamakura, presided over by Nanzen-ji. A second tier of the system consisted of Ten Temples. This system was extended throughout Japan, effectively giving control to the central government, which administered this system. The monks, often well educated and skilled, were employed by the "shōgun" for the governing of state affairs.

Rinzai-monasteries.

Not all Rinzai Zen organisations were under such strict state control. The Rinka monasteries, which were primarily located in rural areas rather than cities, had a greater degree of independence. The Ōtōkan lineage, which centered on Daitoku-ji, also had a greater degree of freedom. It was founded by Nanpo Shōmyō, Shūhō Myōchō, and Kanzan Egen. A well-known teacher from Daitoku-ji was Ikkyū.  Another Rinka lineage was the Hotto lineage, of which Bassui Tokushō is the best-known teacher.

Tokugawa (1600–1868).

By the 18th century, the Rinzai school had entered a period of stagnation and decline. At that time, the monk Hakuin Ekaku (1686–1769) became prominent as a revitalizer and organizer of Rinzai Zen, and his vigorous methods spearheaded a long-lasting revival. Hakuin's systemization of the kōan training system serves today as the framework of formal Rinzai practice.

Hakuin.

Most Rinzai lineages pass through Hakuin Ekaku, the 18th century revivalist, who considered himself to be an heir of Shōju Rōnin (Dokyō Etan, 1642–1721), though Hakuin's formal dharma transmission from Shōju Rōnin entails some unanswered questions. When he was installed as head priest of Shōin-ji in 1718, he had the title of "Dai-ichiza", "First Monk": All contemporary Rinzai-lineages stem from Inzan Ien (1751–1814) and Takujū Kosen (1760–1833), both students of Gasan Jitō (1727–1797). Gasan is considered to be a dharma heir of Hakuin, though "he did not belong to the close circle of disciples and was probably not even one of Hakuin's dharma heirs".  Through Hakuin, all contemporary Japanese Rinzai-lineages are part of the Ōtōkan lineage, brought to Japan in 1267 by Nanpo Jomyo, who received his dharma transmission in China in 1265.

Meiji Restoration (1868–1912) and Imperial Expansionism (1912–1945).

During the Meiji period (1868–1912), after a coup in 1868, Japan abandoned its feudal system and opened up to Western modernism. Shinto became the state religion, and Buddhism adapted to the new regime. Within the Buddhist establishment the Western world was seen as a threat, but also as a challenge to stand up to.  A Rinzai university was founded in 1872, Hanazono University, initially as a seminary for those entering the priesthood.

Teachings and practice.

Rinzai Zen is marked by the emphasis it places on kenshō ("seeing one's true nature") as the gateway to authentic Buddhist practice, and for its insistence on many years of exhaustive post-kensho training to embody the free functioning of wisdom within the activities of daily life.  Training focuses on zazen (seated meditation), kōan, and samu (physical work done with mindfulness).  When engaged in zazen, kōans are frequently the object of meditation, while shikantaza ("just sitting") is less emphasized, but still used. This contrasts with Sōtō practice, which has de-emphasized kōans since Gentō Sokuchū (circa 1800), and instead emphasizes shikantaza. In general, the Rinzai school is known for the rigor and severity of its training methods.  The Rinzai style of Zen practice may be characterized as somewhat martial or sharp (following in the spirit of Linji Yixuan). In this regard, Rinzai is often contrasted with another sect of Zen deeply established in Japan, Sōtō, which has been called more gentle and even rustic in spirit. A Japanese saying reflects these perceptions: "Rinzai for the Shōgun, Sōtō for the peasants" (臨済将軍、曹洞土民, "Rinzai Shōgun, Sōtō Domin").

Contemporary Rinzai schools.

Rinzai Zen in Japan today is not a single organized body. Rather, it is divided into 15 branches (or 16, if Ōbaku is included), referred to by the names of their head temples, of which half are based in Kyoto (8, plus Ōbaku). The largest and most influential of these is the Myōshin-ji branch, whose head temple was founded in 1342 by Kanzan Egen (1277–1360). Other major branches include Nanzen-ji and Tenryū-ji (both founded by Musō Soseki), Daitoku-ji (founded by Shūhō Myōchō), and Tōfuku-ji (founded by Enni Ben'en, 1202–1280). These branches are purely organizational divisions arising from temple history and teacher-student lineage, and do not represent sectarian divides or fundamental differences in practice. There are nevertheless small differences in the way kōans are handled.  These head temples preside over various networks, comprising a total of approximately six thousand temples, forty monasteries, and one nunnery. The Myōshin-ji branch is by far the largest, approximately as big as the other branches combined: it contains within it about three thousand five hundred temples and nineteen monasteries.

Japanese Rinzai schools.

The 15 branches of Rinzai, by head temple, are:

Related Japanese Zen schools.

Obaku.

Aside from Rinzai and Sōtō, there is a third tradition of Zen present in Japan, the Ōbaku Zen sect. It was brought to Japan in the 17th century, and shows significant influence from the Pure Land school. This reflects the syncretistic tendencies that developed in Chinese Buddhism in the centuries after the earlier Rinzai lines had been transmitted to Japan.  Ōbaku is also descended from the Chinese Linji school, and so technically may be considered a part of the Japanese Rinzai movement; further, its abbots are now part of the same Ōtōkan lineage as Rinzai branches, though they were not so originally (instead following a more recent Chinese lineage). While Manpuku-ji, the Ōbaku headquarters temple, is considered one of the 15 Rinzai branches mentioned above, Ōbaku Zen is administratively separate from the other 14 branches and continues to maintain its own distinct identity.

Fuke.

A final Japanese Zen sect that self-identified as descending from the Linji school was the Fuke sect; Fuke Zen was suppressed with the Meiji Restoration in the 19th century and no longer exists. Its influence on the development of music for the shakuhachi (bamboo flute), however, has been great.

Ichibata Yakushi Kyodan.

Ichibata Yakushi Kyodan (properly written Ichiba Yakushi Kyōdan 一畑薬師教団) is today generally considered an independent school of Buddhism, though it was previously associated with Myōshin-ji (and before that Tendai), and may still be considered part of Rinzai, though its practices and beliefs have little in common with Rinzai. It places great importance in faith in Yakushi (Medicine Buddha), and is known as a destination for healing.

Western Rinzai schools.

A number of Rinzai lines have been transplanted from Japan to Europe, the Americas, and Australia, and non-Japanese practitioners have been certified as teachers and successors of those lineages. Rinzai temples, as well as practice groups led by lay practitioners, may now be found in many nations.  North American Rinzai centers include Rinzai-ji founded by Kyozan Joshu Sasaki Roshi in California, Dai Bosatsu Zendo Kongo-ji established by Eido Shimano Roshi and Soen Nakagawa Roshi in New York, Chozen-ji founded by Omori Sogen Roshi in Hawaii, Daiyuzenji in Illinois and Korinji in Wisconsin both founded by dharma heirs in Omori Sogen Roshi's line, and Chobo-Ji founded by Genki Takabayshi Roshi in Seattle, Washington. In Europe there is Havredal Zendo established by a Dharma Heir of Eido Shimano, Egmund Sommer (Denko Mortensen).

Cultural influence.

Remarkable results of the early relationship between Rinzai Zen and the ruling classes were a strong Rinzai influence on education and government, and Rinzai contributions to a great flowering of Japanese cultural arts such as calligraphy, painting, literature, tea ceremony, Japanese garden design, architecture and even martial arts. A perhaps unanticipated result is that Soto Zen temples, with their connection and appeal to commoners, eventually came to outnumber Rinzai temples.

The Rinzai school (; Japanese: "Rinzai-shū", ) is one of three sects of Zen in Japanese Buddhism (with Sōtō and Ōbaku being the others).

Rinzai šú (: 臨済宗 "Rinzai šú"; : "línjì zōng"), také Rinzai, je vedle školy Sótó a Óbaku jedna z velkých škol japonského zenového buddhismu. Do Japonska ji jako první přenesl z Číny buddhistický mnich Eisai Zendži (1141-1215), který se v roce 1168 vydal do Číny, aby zde studoval buddhistickou nauku.


Origins.

In the late 1960s, Hewlett-Packard (HP) manufactured various automated test and measurement instruments, such as digital multimeters and logic analyzers. They developed the "HP Interface Bus (HP-IB)" to enable easier interconnection between instruments and controllers (computers and other instruments).  The bus was relatively easy to implement using the technology at the time, using a simple parallel bus and several individual control lines. For example, the HP 59501 Power Supply Programmer and HP 59306A Relay Actuator were both relatively simple HP-IB peripherals implemented in TTL, without the need for a microprocessor.  HP licensed the HP-IB patents for a nominal fee to other manufacturers. It became known as the General Purpose Interface Bus (GPIB), and became a de facto standard for automated and industrial instrument control. As GPIB became popular, it was formalized by various standards organizations.

Standards.

In 1975, the IEEE standardized the bus as "Standard Digital Interface for Programmable Instrumentation", IEEE 488; it was revised in 1978 (producing IEEE 488-1978). The standard was revised in 1987, and redesignated as IEEE 488.1 (IEEE 488.1-1987). These standards formalized the mechanical, electrical, and basic protocol parameters of GPIB, but said nothing about the format of commands or data.  In 1987, IEEE introduced "Standard Codes, Formats, Protocols, and Common Commands", IEEE 488.2. It was revised in 1992. IEEE 488.2 provided for basic syntax and format conventions, as well as device-independent commands, data structures, error protocols, and the like. IEEE 488.2 built on IEEE 488.1 without superseding it; equipment can conform to IEEE 488.1 without following IEEE 488.2.  While IEEE 488.1 defined the hardware and IEEE 488.2 defined the protocol, there was still no standard for instrument-specific commands. Commands to control the same class of instrument, "e.g.", multimeters, varied between manufacturers and even models.  The United States Air Force, and later Hewlett-Packard, recognized this as a problem. In 1989, HP developed their TML language which was the forerunner to Standard Commands for Programmable Instrumentation (SCPI), introduced as an industry standard in 1990. SCPI added standard generic commands, and a series of instrument classes with corresponding class-specific commands. SCPI mandated the IEEE 488.2 syntax, but allowed other (non-IEEE 488.1) physical transports.  The IEC developed their own standards in parallel with the IEEE, with IEC 60625-1 and IEC 60625-2 (IEC 625), later replaced by IEC 60488.  National Instruments introduced a backward-compatible extension to IEEE 488.1, originally known as HS-488. It increased the maximum data rate to 8 Mbyte/s, although the rate decreases as more devices are connected to the bus. This was incorporated into the standard in 2003 (IEEE 488.1-2003), over HP's objections.  In 2004, the IEEE and IEC combined their respective standards into a "Dual Logo" IEEE/IEC standard IEC 60488-1, "Standard for Higher Performance Protocol for the Standard Digital Interface for Programmable Instrumentation - Part 1: General", replaces IEEE 488.1/IEC 60625-1, and IEC 60488-2,"Part 2: Codes, Formats, Protocols and Common Commands", replaces IEEE 488.2/IEC 60625-2.

Characteristics.

IEEE 488 is an 8-bit, electrically parallel bus which employs sixteen signal lines — eight used for bi-directional data transfer, three for handshake, and five for bus management — plus eight ground return lines.  The bus supports 31 five-bit primary device addresses numbered from 0 to 30, allocating a unique address to each device on the bus.  The standard allows up to 15 devices to share a single physical bus of up to total cable length. The physical topology can be linear or star (forked). Active extenders allow longer buses, with up to 31 devices theoretically possible on a logical bus.  Control and data transfer functions are logically separated; a controller can address one device as a "talker" and one or more devices as "listeners" without having to participate in the data transfer. It is possible for multiple controllers to share the same bus, but only one can be the "Controller In Charge" at a time.  In the original protocol, transfers use an interlocked, three-wire "ready–valid–accepted" handshake. The maximum data rate is about one megabyte per second. The later HS-488 extension relaxes the handshake requirements, allowing up to 8 Mbyte/s. The slowest participating device determines the speed of the bus.

Connectors.

IEEE 488 specifies a 24-pin Amphenol-designed micro ribbon connector. Micro ribbon connectors have a D-shaped metal shell, but are larger than D-subminiature connectors. They are sometimes called "Centronics connectors" after the 36-pin micro ribbon connector Centronics used for their printers.  One unusual feature of IEEE 488 connectors is they commonly use a "double-headed" design, with male on one side, and female on the other. This allows stacking connectors for easy daisy-chaining. Mechanical considerations limit the number of stacked connectors to four or fewer, although a workaround involving physically supporting the connectors may be able to get around this.  They are held in place by screws, either UTS (now largely obsolete) or metric M3.5×0.6 threads. Early versions of the standard suggested that metric screws should be blackened to avoid confusion with the incompatible UTS threads. However, by the 1987 revision this was no longer considered necessary because of the prevalence of metric threads.  The IEC 60625 standard prescribes the use of 25-pin D-subminiature connectors (the same as used for the parallel port on IBM PC compatibles). This connector did not gain significant market acceptance against the established 24-pin connector.

Capabilities.

More information see Tektronix.

Use as a computer interface.

HP's designers did not specifically plan for IEEE 488 to be a peripheral interface for general-purpose computers; the focus was on instrumentation. But when HP's early microcomputers needed an interface for peripherals (disk drives, tape drives, printers, plotters, etc.), HP-IB was readily available and easily adapted to the purpose.  HP computer products which used HP-IB included the HP series 80, HP 9800 series, the HP 2100 series, and the HP 3000 series. HP computer peripherals which did not utilize the RS-232 communication interface often used HP-IB including disc systems like the HP 7935. Some of HP's advanced pocket calculators of the 1980s, such as the HP-41 and HP-71B series, also had IEEE 488 capabilities, via an optional HP-IL/HP-IB interface module.  Other manufacturers adopted GPIB for their computers as well, such as with the Tektronix 405x line.  The Commodore PET (introduced 1977) range of personal computers connected their peripherals using the IEEE 488 bus, but with a non-standard card edge connector. Commodore's following 8-bit machines utilized a serial bus whose protocol was based on IEEE 488. Commodore marketed an IEEE 488 cartridge for the VIC-20 and the Commodore 64. Several third party suppliers of Commodore 64 peripherals made a cartridge for the C64 that provided an IEEE 488-derived interface on a card edge connector similar to that of the PET series.  Eventually, faster, more complete standards such as SCSI superseded IEEE 488 for peripheral access.

Comparison with other interface standards.

Electrically, IEEE 488 used a hardware interface that could be implemented with some discrete logic or with a microcontroller. The hardware interface enabled devices made by different manufacturers to communicate with a single host. Since each device generated the asynchronous handshaking signals required by the bus protocol, slow and fast devices could be mixed on one bus. The data transfer is relatively slow, so transmission line issues such as impedance matching and line termination are ignored. There was no requirement for galvanic isolation between the bus and devices, which created the possibility of ground loops causing extra noise and loss of data.  Physically, the IEEE 488 connectors and cabling were rugged and held in place by screws. While physically large and sturdy connectors were an advantage in industrial or laboratory set ups, the size and cost of the connectors was a liability in applications such as personal computers.  Although the electrical and physical interfaces were well defined, there was not an initial standard command set. Devices from different manufacturers might use different commands for the same function. Some aspects of the command protocol standards were not standardized until Standard Commands for Programmable Instruments (SCPI) in 1990. Implementation options (e.g. end of transmission handling) can complicate interoperability in pre-IEEE 488.2 devices.  More recent standards such as USB, FireWire, and Ethernet take advantage of declining costs of interface electronics to implement more complex standards providing higher bandwidth. The multi-conductor (parallel data) connectors and shielded cable were inherently more costly than the connectors and cabling that could be used with serial data transfer standards such as RS-232, RS-485, USB, FireWire or Ethernet. Very few mass-market personal computers or peripherals (such as printers or scanners) implemented IEEE 488.

IEEE 488 is a short-range digital communications 8-bit parallel multi-master interface bus specification developed by Hewlett-Packard as HP-IB (Hewlett-Packard Interface Bus). It subsequently became the subject of several standards, and is generically known as GPIB (General Purpose Interface Bus).

GPIB (General Purpose Interface Bus, někdy nazývané IEEE 488, HP-IB (Hewlett Packard IB) nebo IMS (International Measurement System), je rozhraní pro měřicí a zkušební přístroje a zařízení, které umožňuje přenos dat mezi dvěma nebo více přístroji. Umožňuje připojení počítače, který může řídit přenos dat. Rozhraní bylo vyvinuto v roce 1972 společností Hewlett-Packard a později se stalo jedním z nejrozšířenějších komunikačních systémů pro měřicí a zkušební techniku na světě. Jeho využití bylo původně navrženo pro propojení měřicích přístrojů v rámci jedné či několika laboratoří. Základní myšlenkou je využití autonomních jednotek, které sdílejí informace s ostatními jednotkami pomocí sběrnice. V roce 1975 bylo rozhraní přijato jako standard IEEE 488 "Standard Digital Interface for Programmable Instrumentation".


Geography.

Although not the capital, most of the businesses are in Borgo Maggiore. It is the third largest city in the country, after Dogana and Borgo Maggiore. It borders the San Marino municipalities Acquaviva, Borgo Maggiore, Fiorentino, and Chiesanuova and the Italian municipality San Leo.  Akademio Internacia de la Sciencoj San Marino is centered here.

History.

"Due to its being the capital and previously the only city in San Marino, the history of this city is almost the same as the History of San Marino. For more information on that topic, see that article."  The city was founded by Saint Marinus and several Christian refugees in the year 301. From then on the city became a center of Christian refugees who fled from Roman persecution.  The urban heart of the city was protected by three towers: the first, Guaita, constructed in the 11th century, was famous for being impenetrable, which to a great extent discouraged attacks on the city.  Due to the Crusades, it was felt necessary to construct a second tower, Cesta (13th century). But the Sanmarinense defensive system was not completed until the construction of a third tower, the Montale (14th century) - the smallest of all and constructed on the last of the summits of Monte Titano.  With the population of the city increasing, the territory of the country was extended by a few square kilometers. Since the Sanmarinese policy was not to invade or to use war to obtain new territories, it was by means of purchases and treaties that San Marino obtained the other eight "castelli" which make up San Marino.

Parishes.

The City of San Marino has the following 7 parishes or wards ("curazie"):

Economy.

The economy of the city of San Marino has always been closely bound to that of the country. Until recently, the main economic activities of the locality were stone extraction and carving. Today, there is a more varied economy, including tourism, commerce, sale of postage stamps, and a small agricultural industry, although the latter is in decline.

Landmarks.

The city is visited by more than three million people per year, and has developed progressively as a tourist centre. Of the tourists, 85% are Italian. There are also more than a thousand retail outlets, where one can find a great variety of products.

Transport.

The town is known for its long, winding cobblestoned streets, as its altitude and steep approach put it beyond the reach of the San Marino Superhighway. San Marino is also notable in that cars are prohibited in much of the town center.  Before the Second World War, a railway was built from San Marino to Rimini under the dictatorship of Benito Mussolini. Its tunnels, and the railway station 'Piazzale Lo Stradone', still exist. Proposals for the reopening of this railway have been presented to the government on several occasions, but thus far without action.  There is a regular bus service to Rimini, and a cable car line connects the capital with Borgo Maggiore.  A series of lifts also connects the upper part of town with the lower.

Sports.

The city of San Marino has two football teams: the S.S. Murata and the S.P. Tre Penne. The city had the Olympic Flame pass through San Marino during the run-up to the 2006 Winter Olympics.

International relations.

Twin towns—Sister cities.

The City of San Marino is twinned with:

The City of San Marino ("Italian": Città di San Marino) (also known simply as San Marino or locally as Città) is the capital city of the Republic of San Marino, Southern Europe. The city has a population of 4,044. It is on the western slopes of San Marino's highest point, Monte Titano.

San Marino je hlavní město a také samosprávná obec republiky San Marino. Nachází se v západní části země, na západním svahu nejvyšší hory San Marina Monte Titana. Na jejím hřebenu jsou tzv. ""Tři sanmarinské pevnosti"". V roce 2013 zde žilo přes 4 100 obyvatel na rozloze 7,09 km.