A dictionary of electrical words, terms and phrases (1896)
Houston, Edwin J. (Edwin James), 1847-1914 · New York, The W.J. Johnston company · leaf 78
e is placed. Thiscircuit is opened by a spring,on the removal of the pressure.Some forms of push-buttons areshown in Figs. 88, 89 and 90. A floor-push for dining-roomsand offices is shown in Fig.90. Fig. 88 shows the generalappearance oi an ordinary bell-push. The arrangement of theinterior spring…
Electricity · Electrical engineering
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
![An illustration from [Graphophone patents] (1878)](https://img.insideoutlibrary.com/img/200/ia-graphophonepaten20unit-951-429.webp)
