[NA021AAB], Technical Note, Thomas Alva Edison, April 29th, 1889


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[NA021AAB], Technical Note, Thomas Alva Edison, April 29th, 1889

Editor's Notes

[26 pages of notes and drawings of a draft caveat] "Phono EL & Ore Mlg" [3 drawings of diaphragms with figure labels "leverage"; "open"; "glass funnell"] [drawing with text:] Indenting by stretching & use of ball both for indenting and Reproducing [drawing for ore separation labeled "Lift & drop--"] [ore separator drawing with figure labels "dust" and "rake" ] [ore separator drawing with figure labels "overflow," "water," "sieve," "Reciprocating" and text:] Mag-- Washing in magnetic field [ore separator drawing with figure label "air"] [ore separator drawing labeled:] Multiple Duplicator [3 drawings phonograph one labeled "Amplifier] [2 lamp drawings] [drawing with text:] Screen to screen off the scraping sounds Longer waves lengths pass around but short scrap waves the screen throws shadow & stops them [drawing with text:] Rotating Spectacle also put Recorder & Reproducer on same dia & by twisting slightly throw them in & out of line to operate with. Instead of spectacle we could have single arm & hole & use removeably connected Recorders & Reproducers also there could be 2 arms one with Recorder one with Reprodr & both move independently Claim Clamped diapm preferably glass between Lapped disk without yielding material [phono diaphragm drawing with labels "Link" and "center line prevent canting dia"]##for phono-- Brush whose hairs are stiff & run to a point, Deer hair##Closed funnel filled with a heavy Vapor like Chloroform, with or without pressure.##A Turned surface on a phonogram-- a Turned surface on a phonogram in Situ--##a cylinder of Halogenzed Balata or similar gum coated with phonographic Recording material for mailing cylinders also a flexible--##Making a phonogram of a soft material adulterated with or composed wholy of a material which by a subsequent treatment chemically etc will harden say a wax in which aniline oil will mix. Record on it & harden by Sulphuric acid with forms solid Sulphr Analic Compound##Mix parafine with a Hydrocarbon or some hard wax or stearate which will mix with the Hydrocarbon so that it can be worked in the phono & then after record is made chlorinate the surface of the Cylinder to make the liquid Hydrocarbon a Solid derivative##Asphalt mixed with such a Hydrocarbon like Benzol can be so proportioned as to be recorded upon & when Chlorinated by Chlorine or by immersion in an inert solution containing a chlorinating compound will become hardened##Chlorinated Balata when used for non inflammable Insulating purposes is apt to become brittle after the solvents have evaporated to prevent this-- I propose to put Linseed oil with the balata & chlorinate, also Linseed oil & chlorinate with Chloride Sulphur-- Mix Camphor with it-- ree balata-- Rubber-- also gutta percha also Syrian asphalt waxes already Chlorinated. Filiments can be made with Carbon made from finely divided graphite mixes with a carbonizable locking material like asphaltene or highly dehydrogenized asphalt like substance like that produced by oxidizing asphalt by nitric acid or by chlorine which removes the Hydrogen largely or by mixing Sulphur by a solvent with the asphalt disolved with solvent-- Use Asphalt being or not previously chlorinated The dough is squirted in a filiment & carbonized##I act on pulverized magnetic iron ore which have been concentrated as far as possible by an acid to remove the last traces of phosphorous which occurs in the form of phosphate of Lime. I use warm sulphuric acid diluted-- also nitric get the acid back by a centrifugal drier & then work the ore with water to remove the products of the reaction--##For phonograph points I used Chemically pure iron reduced by Hydrogen, form the same into shape & then form the outer surface into sheet by Cementation.##I propose to use Saphire for the shaving tool & Recording & Repdcg points, am conducting experiments to obtain proper machinery to maek them accurately & economically##One process I am experimenting on to mould cheaply phonogram blanks Is to use a screw or hydraulic press and force the cylinders out like lead pipe cut them into proper lengths & then put them in a forming mould while plastic & with a paper mandril inside having a taper surface set them to shape by a blow withdraw from the mould & cool on the maindril--##another method is instead of pouring the material in a liquid state in a proper mould withdrawing the mandril & forcing the cylinder out as now I force the material while in a plastic condition into the mould by a hydraulic press the moulds being removeably connected to the press the press being hot so the material is plastic##For rapid Turning off the cylinders so they may have a true surface I use several shaving knifes following each other but all connected together rigidly allowing each knife to take such a depth of chip as not to chip the surface out for instance if I have 4 Knifes I am enabled to take off 6 times the depth of surface as one Knife The first knife takes a comparatively deep chip the 3nd one not so deep & so on the last knife does the smoothing. by this means going over the cylinder several times to true its surface is unnecessary--[drawing of funnel with text labels "a" and "b" and text:] Funnel made of Spruce wood, the sides quite thin-- so that the sides form a sound prism some portion of the wood from a to b is always in unison in its vibrating period with some sound wave Hence amplification of nearly all the sounds## [drawing funnel with text:] by the waves one side is responsive to all waves below a certain pitch while the other side respond to all above a certain pitch [following text is loose page inserted in book here:] Shaving off knife with determining bob--so always take right depth chip & not guess which causes sometimes the chip not enough to shave previous talking off & another times more than necessary is taken off--##New clamp to clamp swing arm--##New double nut 100 thread arm on spectacle to lift it up--##[ore separator drawings?] [generator drawings with labels "Cut out" and "arc auto Reg"] tio remove the non magnetic particles which cling to the magnetic by cleavage plane I tumble the ore with large rocks after or before concentration to remove the clinging particles & if concentrated I run through the concentrator again [drawing with text:] Hand turning phono for toy figures##The material which I propose for the base of the veneered cylinders may be poured out in sheets & while plastic rolled taper cut in strips & formed into a cylinder around a mandril by bolting or loping or a round disk somewhat thick may while plastic be forced over a mandril to shape or it may be spun over a mandril or the sheets may be forced out when in a plastic state by a press to side & wrapped around a mandril & then trued or narrow strips can be forced from the press & be wound while plastic around mandril just as it it was paper & a cylinder formed & while still soft have the outer surface of the cylinder paralleled ie same diameter outside over whole of the cylinder by a hot iron or tool travelling along while material is rotated##If squirted like lead pipe The thickness of the cylinder walls will be the same but as a Taper inside is required to fit the taper of the phonogram holder of the phonogh & a straight outside The sections of plastic material as the come from the press must be thicker than they are to used when the phonogm is complete, hence by cutting the tube in sections shorter than the finished phonogm & putting on a taper made mandril the tape is made but the outside is now not same diameter. This is made right diameter of its whole length & the phonogram lengthened by spinning by a tool while the mandril is rotated##I make a battery by using say Zinc containing a small per cent of mercury. This I immerse in an acid or alkaline solution such as Sulphuric acid or Sodic Hydrate. The depolarizing electrode I form of Red Oxide of Lead mixed with water or some soluable salt of lead like the acetate or nitrate just sufficient to moisten it then mould it by hydraulic pressure into flat plates. These are sufficiently coherent to be handled. They are then put into a preoxidizing solution say a soluable Hypchlorite or Chlorate of Potash & Hydrochloric acid or dry hyperchlorous gas is passed over them & in fact many methods of raising the lower oxide to a higher one can be used—The warm Hypochlorite is perhaps the most convenient. The plate after peroxidation is suspended in the liquid in a lead frame which makes contact with the plate around all except its top edge= If the liquid is say a 30 per cent solution of Sodic Hydrate the results are very good while the battery is at work but lead gradually goes into solution when the circuit is open & is deposited on the Zinc—My improvement consists in immersing the plates before use in water or an alkaline solution or even weal acetic for several weeks so that all of the unchanged red lead is dissolved out and then when the plates are put in the Regular battery by means of an external conductor keep the battery always working ie doing just enough work internally while not being used for useful purposes to counteract the dissolving rate & thus prevent fouling the Zinc—I am now engaged in experimenting to produce plates chemically which are equal in all respects to the peroxide of Lead plates produced electrolytically as in a storage battery—The peroxide produced electriclytically acts very different from that produced chemically and this is due probably to the intimacy of contact between the particle of peroxide and probably also to the possibility that the chemically prepared peroxide is a hydrate, to produce an anhydrous peroxide of lead I use a plate of read lead made by hydraulic pressure & peroxide it while in a powerful dehydrating solution like hot concentrated Sulphuric acid== saturated solution of Chloride Zinc strong Hydrofluoric acid phosphoric acid & other dehydrating agents. [drawing follows]



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