[LB039033], Letter from Thomas Alva Edison to Campbell Scott, March 24th, 1890
https://edisondigital.rutgers.edu/document/LB039033
Transcription
March 24th 1890 Campbell Scott, Esq., No. 439 Main Street, Louisville, Kentucky Dear Sir:- In reply to your letter under date of February 12th 1890, which was submitted to me upon my return to Orange a few days ago. I would say that, from experiments carried on in the State of New York, with animals, I am certain that it would require the services of an expert electrician, and good conditions, to produce death with 500 Volts of continuous current; but 700 Volts is the limit to which should be used in connection with overhead wires, in all cities where there are many wires. Yours very truly, Thos A. Edison