Spon, Ernest, Haldane, Robert, Lock, Charles G. Warnford (Charles George Warnford), 1853-1909 · London ; New York : E. & F.N. Spon · leaf 215
Electrics — Telephones. 197 3 horse-shoe magnets, putting 2 on the the electro-magnet m, which it mag- table with their opposite poles 4 in. netizes and causes to attract a small apart. Bridge the spaces with 2 files, fiiece of soft iron attached to the spring … s, and produces pressure iu the glass tube t, which is filled with powdered carbon. From the magnet the current passes to a wire introduced into the lower part of t, the bottom of which is stopped with a cork ; from this wire it passes through the powdered carbon to another wire higher up iu the…
Workshop recipes · Technology · Industrial arts
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
![An illustration from [Electric engineering.] (1902)](https://img.insideoutlibrary.com/img/200/ia-electricengineer01inte-230-100.webp)
