Work and Fall begin in Rural Retreat (Telegraph)
NW Mailing List
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Mon Oct 8 14:11:26 EDT 2012
Mr. Frank Akers wrote/asked:
>> I recall PawPaw (J.L.Akers) tending to
the batteries, glass battery jars with crow's feet, but can't recall where
the batteries were housed. Seems to me they were in the 'luggage' area or
perhaps in a closet there? Was there a 'standard' place where the
batteries were kept? Also, what all did the batteries power--just the
telegraph or some of the signals? <<
It's good that you have this memory of your Grandfather !
The batteries in the stations were "local telegraph batteries." Since they contained sulphuric acid and were "made up" in open top glass jars, with loosely fitting porcelain tops laid across the jars, there was a good bit of acid evaporation and that eventually corroded everything within a number of feet. Therefore, they were usually placed in the "ware room" (freight section) of a combination station. In the very old days, they were sometimes placed under the telegrapher's desk. Ugh!
Why were "local telegraph batteries" used? Could the telegraph instruments not be worked off the "line voltage" of the telegraph wires? Without getting into a lot of technical explanation about the electrical properties of telegraph lines and telegraph instruments, suffice it to say that the general practice at "way stations" was to have only a telegraph RELAY on each telegraph wire passing through the station (and on the N&W, there were generally three or four wires.) But a relay gives only a quiet tick-tick as the telegraph circuit transmits its dots and dashes, not the loud clack-clack that is necessary for the telegrapher to copy messages (especially if there is noise in the station or an engine passing by.) Therefore, each way station is equipped with a "local" telegraph SOUNDER which can be "cut in" (using a jack box) on any of the telegraph wires the operator wants to work.
Normally the telegraph operator would keep his "local sounder" plugged into the Train Dispatcher's wire. But if he heard the call for his station (say "AY," which was the telegraph call for Rural Retreat) on one of the other relays (say the relay on the Message wire or the Western Union wire,) he would use his jack box to plug his local sounder into that particular wire and copy the message.
The "local sounder" was almost invariably an instrument wound with 4 ohm coils, requiring 0.250 amps DC (that's one quarter of an amp) to operate. Voltage to operate the local sounder was made using the glass jar primary cells you remember your grandfather tending. Each glass jar was a "cell," and each cell gave about 1.2 volts. Generally about 4 volts was needed to operate the local sounder, which meant that about four "cells," wired in series, were needed. If four cells yielding 1.2 volts are wired in series, you get 4.8 volts or so. (The current [amps] is no problem, as each cell of a primary battery will easily output a quarter amp.)
Each cell consisted of a round, open-top glass jar, perhaps 10 inches in diameter and about 14 inches high. One "plate" of the battery was a chunk of copper (generally hung down the inside of the jar,) and the other plate was a large piece of zinc cast into a crow's-foot pattern and resting on the bottom of the jar. The electrolyte was sulphuric acid plus water, poured into the open top of the jar. One wire from the local sounder was hooked to the copper, and the other to the zinc, using thumb screws. Then a circular, flat porcelain lid was laid across the top of the jar. Usually the lineman would pour a film of "Edison Battery Oil" on the top of the acid/water mix, to keep down evaporation. But over time, some of the water and sulphuric acid would evaporate, and what you observed was your grandfather adding water to the cells to bring them up to the proper level. Eventually both the copper and the zinc would be consumed by the galvanic process, at which point the telegraph lineman would dump out the entire contents of each cell and re-build the battery with fresh coppers, zincs and acid.
Remember, all this technology was refined and put in place long before the days of storage batteries and trickle charging... and there was no such thing as "rural electrification." If you needed voltage out of the railroad, you "made" it with primary battery cells ! The low voltage/low current requirement of the early track circuits for railroads (which originated in 1872) is precisely the historical reason that track circuits even today generally operate at less than 4 volts !
-- abram burnett
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