Easy electrical experiments and how to make them; (1918)
Dickinson, Leonard Perley, 1874- [from old catalog] · Chicago, F. J. Drake & co · leaf 191
tened very firmly to the shaft, the onlyrequisite being that it shall not slip on the shaft when thelatter turns. It should be of such size that the shaft whichcarries the minute hand of the clock, (that is the longhand), shall make one revolution in about half a minute. Remove the gear wheel which… … Clockwork Mechanism of Fire Alarm thick. Notches are cut in this disc as shown, the notchesbeing 3-16 inch wide, and the space between them is of thesame width. Starting at the part of the disc which isuppermost, cut three such notches, properly spaced, thenleave a space of %-inch and cut four…
Electric apparatus and appliances · Electricity
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
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