[LB040189], Memorandum, Edison Lamp Co, April 25th, 1890
https://edisondigital.rutgers.edu/document/LB040189
Transcription
April 25, 1890 Edison Lamp Company Harrison, N.J. SULPHIDE OF SILVER This was an experiment on a system for cutting out automatically municipal lamps in series when anyone in the series broke it was successful as far as carried out, and the results have been communicated to the Lamp Company. VOLT METER EXPERIMENT This is a branch of the experiment on Sulphide of Silver in connection with municipal lamp cut outs. PHOTOMETER This was an experiment made to ascertain whether a voltmeter could be made cheaply on the photometer principle.