JF Ptak Science Books Post 2075 History of Holes series
While grazing through the 1859 volumes of the Comptes Rendus1, looking around for anything having anything to do with Mr. Darwin and his Big Book published later in this year (on 24 November), I got a little lost as usual, and was digging around the early months, and came upon the drawing above. Mostly I was attracted to it for the holes, as there is a longish thread/series on this blog devoted to the History of Holes, and though at first blush that it might actually be a Runic something, or Islander counting stick. When I actually started to read the article it was none other than the recording strip for telegraphy, devised by Charles Wheatstone (1802-1875), famous for his Wheatstone bridge and for his experimental determination of the speed of electricity2). Now the recorder part of this was not on the receiving end, but rather on the sending--Wheatstone devised a way of recording the strokes of a telegrapher's key and translating them into two rows of holes; the message was recorded on the strip of paper and then fed into a machine that would do the keywork, using the punched paper tape to control the transmitter--it turns out to have been a significantly faster method than by simply having messages struck by human operators, which was abig deal at the time because of the expense of sending telegraphic messages, reaching speeds of 130 wpm early on (and then 300-400 wpm later on a good circuit)3.
Holes made appearances in earlier recording telegraphs, the first going back as far as the beginning of electromagnetic telegraphy goes, with Morse and Vail in 1837--but here we had this fine example, from the excellent Wheatstone, and so I'll stay with that.
Notes:
1. The Scientific Papers of Charles Wheatstone, full text [in French] here.
2. His results were excellent though early-on the speed was slightly greater than what we know know to be the speed of light. His 1834 experiment is found here, along with an illustration of the revolving mirror Wheatstone used, an idea which would find more use in the next decade in the determination of the speed of light experiments.
3. "The system consisted of a perforator, transmitter and receiver. Holes side by side sent a dot, and staggered holes sent a dash. Polarized pulses were used, two of opposite polarity for each dot or dash, received by a sensitive polarized relay. The receiver was essentially a sensitive Morse register that inked a tape, which was later transcribed in the usual fashion. Wheatstone's automatic transmitter was used on the busy lines of the Electric and International Telegraph Company between London and Manchester, Glasgow, Edinburgh and Newcastle. The Wheatstone was very convenient for sending the news, since only one tape had to be made for transmission of the same news to numerous offices."--from this lovely site, here, by Dr James B. Calvert, Associate Professor Emeritus of Engineering, University of Denver: The Electromagnetic Telegraph, a technical history of the 19th-century electromagnetic telegraph, with special reference to the origin and variey of the alphabets, or codes, that were used.
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