[LB055139], Letter from Alfred Ord Tate to Bernard James Harrington, January 12th, 1892
https://edisondigital.rutgers.edu/document/LB055139
Transcription
[illegible text]. January 12, 1892. Prof. B.J. Harrington, McGill University, Montreal, Canada. Dear Sir:- Replying to your letter of 29th ultimo addressed to Mr. Edison, I beg to say with relation to mica as applied in practical application for electrical machines that it is of far more importance it should be mechanically workable than of the very highest chemical purity, provided of course that the insulation can be reasonably maintained. On this account it is much more essential that the brand of mica should be cheap and easily worked by the mechanic than that it should possess a very high electrical or chemical condition, although of course these latter would be independent advantages. Yours very truly, A. O. Tate Private Secretary. M.