[D8624R], Letter from Edward Hibberd Johnson to Thomas Alva Edison, 1886

Item

Abstract

I want you to do some experimental work for the Sprague Co. I want the best brush for running both ways with the same brush. ##A soft elastic brush[?] of sufficient area to carry the current, but which area will not decrease[?] by wear is the real desideratum. ##A tangential[?] brush of flat laminated strips is good until it concaves, then it is hell. Hard brushes, as solids, etc., are harsh and crude. The soft touch of your standard dynamo brush is an absolute essential. We have adopted silicon bronze for commutator bars to the practical extinction of commutator depreciation. Now we want a non-changeable brush contact. How shall we get it? [Sketch is attached to note on final page.]

Date

1886-00-00

Decade

1880-1889

Type

Subject

Identifier

D8624R

Folder Set

D8624

Title

[D8624R], Letter from Edward Hibberd Johnson to Thomas Alva Edison, 1886

Microfilm ID

73:265

Publisher

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