“The air pump is an instrument for removing air from a given space. A closed vessel R is called the receiver, and the space that it encloses is that from which it is desired to remove the air. It is usually made of glass, and the edges are ground so as to be perfectly air-tight. When made in the form shown, it is called a bell-jar receiver.” — Hallock, 1905
V. I. Hallock I.C.S. Refrence Library (Scranton: International Textbook Company, 1905)
1840×2400, 1.1 MiB
785×1024, 156.1 KiB
490×640, 74.9 KiB
245×320, 22.1 KiB