[LB014283], Letter from Samuel Insull to Francis Robbins Upton, October 13th, 1882


View document with UniversalViewer   → View document on Archive.org  → Re-use this digital object via a IIIF manifest


[LB014283], Letter from Samuel Insull to Francis Robbins Upton, October 13th, 1882

Editor's Notes

Mr Edison has directed me to send you following extract from a letter received by Mr Edwd H Johnson from a friend at present in London and who was one of the American Jurors at the Electrical Exhibitions at Paris & London:-##"I have informed you that the Lamp Tests are coming out strongly in favor of Swan. I was most disagreeably surprised to learn this but there can be no doubt that Swan has a wonderfully good lamp and is making improvements day by day Edison is ahead on the score of resistance but by using a smaller filament and higher potential he (Swan) has obtained wonderful results. The lamps are thoroughly well made and the conviction has come to me in a way I cannot mistake. That he has the best lamp is well known today. It is well that Edison should know this as early as possible and be governed accordingly. Mark this the coming carbon is the carbon which before being carbonized is treated by Swans process or some other process. I told you in my last letter that I had seen lamps of his 100 ohms hot, 20 candles, 86 volt amperes, .6 ampere. This will give 400 candles per Electrical Horsepower"




Folder/Volume ID


Microfilm ID


Document ID



Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University
Download CSV | JSON