History, theory, and practice of the electric telegraph (1866)
Prescott, George B.(George Bartlett),1830-1894 · Boston, Ticknor and Fields · leaf 50
cylinder of porous earthic place of the porous cylinder of organic matter in which arecontained the diluted sulphuric acid and the cylinder of zinc,we obtain Bunsens pile. Each carbon cylinder carries at itsupper part a collar of copper, furnished with an appendix, whichis placed in contact, by… … fig. 10. ries the copper ring shall rise above the glass vessel, and conse-quently shall in no way be in contact with the nitric acid. How-ever, as the charcoal is very porous, the capillarity causes theacid finally to attain to the top of the cylinder, and to alter inte-riorly the copper ring.…
Telegraph
Internet Archive · Medical Heritage Library · Public Domain Mark 1.0. Free to use for anything.
![An illustration from [Graphophone patents] (1878)](https://img.insideoutlibrary.com/img/200/ia-graphophonepaten02unit-110-43.webp)
