[NA023205], Technical Note, Thomas Alva Edison, March 21st, 1889
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Title
[NA023205], Technical Note, Thomas Alva Edison, March 21st, 1889
Editor's Notes
[draft] Phono & EL Caveat The use of Chromium for phono point & Tool-- Use of pure Iron by reduction from pure salt Say Reduction by Hydrogen then working into shape making it steel by cementation & then grinding-- [Phono part drawing "Multiple Listeners"] the amount being sufficient to dehydrogenized the Asphalt & prevent melting during carbonization-- Also the Asphalt may be dried after purification & made into a paste with Chloroform & strong Sulphuric acid squirted & the fils. The Sul acid at high temp reduces or enters into combn to prevent melting & SO2 going off as a gas-- Iodine may also be disolved in Bisulphide of Carbon & on Evaporation the Iodine will act as a dehydrogenizer.##Oxide of mercury can be mixed with the asphaltic material and on Carbonizaation the O will dehydrogenize the Asphaltic material & the Hg will go off ion vapor thus leaving the filiment free.##By disolving the material after heating to drive off the very high volitile constituents in chloroform or other go solved not materially acted on by Chlorine. The Chlorine may be passed through the solution until maximum deydrogenzation is obtained-- afterwards to obtain a higher or greater dehydrogzn of the materil & thus will depend on the material the solution may be treated with nitric acid one taom of ) takes out H##Certain kinds of asphalt like purified Trinidad or Hard Cubian ater purification by solvents wherein the ash is taken out, may be boiled in a very flat dish constantly stirring atmospheric oxidation takes place at the same time the more volitile consiuents are driven off and a point is reached when the material only remains soft at 400 C. In this state it may be squirted into filiments by heat round the die of the press by slow carbonization The remaining hydrogen can be driven off & the filiment fully carbonized without distortion.##I have found as a rule that all that portion which is disolved out of an asphaltic residue or mineral coal like Lignites or semi coals is prefereable for this purpose to that disolved out by other solvents##The greatly dehyrogenized material of the asphaltic or Bituminous character stated has other solvents especially when aided by heat but the solvent action also greatly depends on the original nature of the material of which the residue came & also on the character of the reaction involved in deydrogenzing it to the non melting point among Solvents are Methyl alcohol, Chloral Hydrate, Oil Mybane Aniline Oil, Oil Camphor Esculaptious Oil Nitric Ether Nitriet of Amyl Sulpho-Hydrocarbon liquids like Sulpho-carymethylaminc oil mustard & several other Sulpho Compounds##Hollow filiments may be squirted in the same manner as lead pip & hollow Maccaroni. The advantage of hollow filiments are great with Large Candle power Lamps as it gives a more even carbonization throughout the mass--##A carbon filiment made from matter produced by the natural asphaltic material##A filiment for Carbonization formed from a plastic mass##A filiment for carbonization formed from a plastic mass knowns as pitch asphalt [bunch of overstruck text] or rendered infuisble before carbonization by chemical agency--#A filiment of Carbon made frm the ultimate decomposition of Organic materials known as pitches asphalts or Bitumens [bunch of overstruck text] Carbonaceous plastic material capable of being softened by heat or solvents formed into filimens by mechanical means and then subjected to a chemical action whereby that element which renders them fusible is displaced##A filiment of Carbon for an incandescent Lamp made from pitchy Asphaltic or Bituminous products from the decompsoition of organic material either artificial or natural.##Same & add-- made infuisible before carbonization;##Same-- dehydrogenized by chemical agency to render such compounds infusible during the act of carbonization.
Author
Date
1889-03-21
Type
Folder/Volume ID
NA023-F
Microfilm ID
99:405
Document ID
NA023205
Publisher
Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University