National Telegraphic Union · New York : N.T.U. · leaf 132
ns are separated fromeach other by a regular and uniform space of the l-600th to thel-800th of an inch, the layers separated by thin paper. In helices ofsilk insulated wire, the space occupied by the silk is the l-150th tothe l-3C0th of an inch ; therefore a spool made of a given length andsize of… … I ELfc
Telegraph
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