[N023073], Technical Note, Thomas Alva Edison, February 22nd, 1879


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


[N023073], Technical Note, Thomas Alva Edison, February 22nd, 1879

Editor's Notes

conceived the idea of using a bobbin or iron wire wound on lime iwth mplatinum for the last layer the iron and platinum to be pyro-insulated by acetate of magnesia and the size and rest'nce of the iron made so that when it was at a bright yellow approaching white that the plaina should be incandescent. I effect this by using an iron wire slightly loarger than the platinum. made some tests with iron and platina wire joined together & placed between supported and heated with the battery. I find not the slightest difficulty in so selecting the size of the wires that hte pt shall be brilliantly incandescent whiule the iron is yello. Hence I can make a lamp with 1 inch of incandescent surface (pt) with a large resistance, the inner wire of iron losing all of its heat through the platina,, this is a gain in economy of plant.



Folder/Volume ID


Microfilm ID


Document ID



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