Modern practice of the electric telegraph : a handbook for electricians and operators (1874)
Pope, Frank L., 1840-1895 · New York : D. Van Nostrand · leaf 119
.—Several modificationsof the Daniell battery (19), especially adapted to tele-graphic use, are finding much favor within the past fewyears. The most economical and generally useful ofthese improved forms is the gravity battery. The bestarrangement is that known as the Callaud. Anothercombination… … Fig. 56. solutions being prevented from mingling by the differ-ence of their respective specific gravities. The zincplate of the Callaud element, in the form of a shorthollow cylinder, open at both ends, is suspended in theupper portion of the containing jar, as shown in Fig.56, by means of three…
Telegraph
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
