Experimental science. Elementary, practical and experimental physics (1890)
Hopkins, George M. (George Milton), 1842-1902 · New York, Munn & co. · leaf 522
Fig. 486.—Armature Core. Fig. 4S9.—End View of Armature, showingCommutator. Fig. 490,—Brush-holding Disk. … Transverse Section. carefully constructed, will certainly give satisfaction. Onlysuch materials as may be procured anywhere are required.No patterns or castings are needed. Beginning with the armature, a wooden spool, A (Fig.486), should be made of sufficient size to receive the soft 500…
Physics · Lantern projection · Electric apparatus and appliances
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