The standard electrical dictionary; a popular dictionary of words, terms, and phrases, used in the practice of electrical engineering (1897)
Sloane, T. O'Conor (Thomas O'Conor), 1851-1940 · New York, H. W. Henley & co. · leaf 412
Fig-- 257- Perforator for Wheatstones Automatic Telegraph. Perforators may be entirely mechanical but are sometimespneumatic, compressed air being used to operate them. The holesthey make are on different levels of the paper strip, as shown inthe cut. Period. The time required for the completion of…
Electricity
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