[D8227E], Letter from Charles Lorenzo Clarke to Thomas Alva Edison, May 17th, 1882


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[D8227E], Letter from Charles Lorenzo Clarke to Thomas Alva Edison, May 17th, 1882

Editor's Notes

Clarke happy with test of 250 light machine; runs at rated voltage at 900 rpm. "This will have ample margin for regulation and loss on conductors to a considerable amount., or you may reduce the speed." No spark and pressure on brushes just enough to hold them on. In contrast, "The Z machine unfortunately has not margin enough in field to admit of placing the brushes where there is not spark, excepting with a very light load." Lengthy discussion of core dimensions. "I propose to start up with no amalgam on commutator. How about that, and shall experiments be continued on that copper amalgam deposit on brush wires? Something may come of it." Stuart of S Amer has ordered 200 meters, w/o thermoregulators. Lengthy discussion/recommendation abt moulds. "Batchelor is loudly calling for that Frenchman who assists Claudius, and he wants to go to France." But Clarke doesn't want to part with him unless Logan can find someone else who speaks German so that he can understand Claudius." Discussion of breakage of bottles. "Big bug in Bergmann's brass mounted sockets. This sketch shows that the safety-catch connects outside of the wooden part of the socket at both ends." Causes arcing to brass case. "I cannot say that a fire is at all likely but underwriters would doubtless think differently." Clarke favors omitting safety catches in sockets and fixtures. "The first armature is in position at Central Station."




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Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University
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