The standard electrical dictionary : a popular encyclopaedia of words and terms used in the practice of electrical engineering (1898)
Sloane, T. O'Conor (Thomas O'Conor), 1851-1940 · London : Crosby Lockwood and Son · leaf 21
ht. There are many types. Mercurial air pumpsare largely used for exhausting incandescent lamp chambers. (SeeGeissler Air Pump,—Sprengel Air Pump.) Air Pumps, Short Fall, A mercurial air pump in which thefall of mercury or the height of the active column is comparativelysmall. It is effected by… … Burglar Alarm Switch or Circuit Breaker. Alarm, Burgiar. A system of circuits with alarm bell extend-ing over a house or apartments designed to give notice of the open-
Electricity
Internet Archive · Medical Heritage Library · Public Domain Mark 1.0. Free to use for anything.
