es mildly acidic to sweet.
- Daguerreotypes are photographs made on a plate of chemically treated metal.
- The Earth encounters the Leonid meteor swarm -- a ring of particles revolving around the sun -- every November. Sound from meteorites exploding when they hit the ground or atmosphere sometimes accompanies their light show.
- The Lyceum movement seeks to make learning available to adults of all economic levels through demonstration, lecture and debate. Often, topics take a scientific spin and prove particularly popular with farmers.
- The American shad spawns in the Susquehanna and other fresh water rivers, migrates to the ocean, where it spends its adult life and returns to its own birthplace to give birth. It takes three to five years at sea for the fish to grow to 20 inches and 4 to 6 pounds.
- Pulaski's Legion, Casimir Pulaski's cavalry command, sought recruits in York for several months in 1779. Pulaski was killed in battle against the British later that year. The Polish count sometimes is called the "Father of the American Cavalry."
- Temperance workers advocated abstinence or moderation in drinking alcoholic beverages. The movement grew in strength in the 19th century. Its crowning accomplishment was the institution of Prohibition. The Women's Christian Temperance Union, known as the WCTU and one of the most vocal temperance organizations, also pushed for women's voting rights. The WCTU advocates alcohol education today.
- Attorney Jeremiah S. Black successfully argued for the winning side in the landmark Supreme Court case "Ex parte Milligan" in 1866. The court unanimously held that military courts cannot supersede civilian courts in time of war. The case stemmed from the trial of anti-war Democrats in an Indiana military court because it lacked confidence in a civilian court to render a fair verdict.
- Civil War regiments are fighting units consisting of 1,000 officers and men, when operating at full strength. Companies consist of 100 men.
- An incandescent lamp produces light and heat when electric current passes through a filament of conducting material in a vacuum. Inventor Thomas Edison developed the carbon-filament light.
- Penn State University's football stadium bears Pennsylvania Gov. James A. Beaver's name.
- Free silver advocates often hail from Democrat-heavy farming areas such as York County. They back coinage of unlimited amounts of silver to increase the amount of money in circulation. Farmers and others with large debts favor ample money in circulation so consumers can pay for the goods they produce. Profits can then be used to retire large debts.