[X059AA], Letter from Thomas Alva Edison to John F Ott, March 6th, 1885



[letterhead of Hotel San Marco; St. Augustine [FLORIDA]] John-- You must make that little Siemens Magneto work on the spark coil. You can try larger & also smaller wire on armature as the present wire may not fit the wire of the induction coil-- also you better see if Bergmanns man cant cast some field magnets of steel the same as Bergmann used in magneto call or if he cannot you can make some of steel= I think you better fool with armature until you get best results from that then make field magnets 1/2 again as strong-- then twice as strong & then 3 times as strong until you get about 1/8 to 3/16 spark-- I want you to press about 100 chalks so you can have them ready by the time I return= You might also make some experiments with chalks by pressing 1/2 dozen of each kind commencing with moderate pressure & increase until four of you on the press could put no more pressure on about 1/2 doz at say pressure of 1 man on short lever 1/2 doz pressure 1 man on long lever 1/2 doz pressure 2 men & 1/2 doz with all the pressure you can get on= Let me know result of the experiment on Repeater with the relays= Don’t forget to try a plate copper over the ends of the soft carbon buttons for Mendenhall-- =Wish you would start some one working the individual calls keeping a record until about 5000 cells are made. Keeping record of every miss and in case it gets out of order the boy to call you and you record exactly what trouble was. Address all letters to me at San Marco Hotel St Augustine Florida









Folder Set



[X059AA], Letter from Thomas Alva Edison to John F Ott, March 6th, 1885

Microfilm ID


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