Major types of positive-displacement pumps include: 1  Roots. 2  Lysholm twin-screw. 3  Sliding vane. 4  Scroll-type supercharger, also known as the G-Lader.
I believe that the first Reich refers to the establishment of the Holy Roman Empire in the 9th century was Charles the Great. The Second Reich was the unification of Germany under the Prussian Kaiser Wilhelm II in 1870. Of course, we all know what the Third Reich was. The First Reich was the Holy Roman Empire. There is little agreement as to when it was founded. Most German historians date the foundation from the coronation of Otto I in 962. That 'empire' had a continuous existence till 1806. The Second Reich was created by Bismarck in 1871 and lasted till 1918.
The period is also known under the names the Third Reich (Drittes Reich, meaning Third Realm or Third Empire, with the Holy Roman Empire and the German Empire being the first two) and the National Socialist Period (Zeit des Nationalsozialismus, abbreviated as NS-Zeit, literally Time of National Socialism).