[D0204AAV], Letter from Robert Rafn to Thomas Alva Edison, September 20th, 1902


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[D0204AAV], Letter from Robert Rafn to Thomas Alva Edison, September 20th, 1902





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


Sept 20, 1902.
To Dr. L. Sell.
[Brother?] St. 22.
Thos. A. Edison Esq
Orange N. J.
Dear Sir:
On the 8th of this month I called you as follows: "Send without paid by first [illegible] sample tested graphite".
The purpose is to show in support of the graphite application, the difference between such treated graphite and some samples of [machine?] graphite processed here in Berlin, and, consequently, that it does not follow as a matter of course, that any [machine?] graphite, when reduced to the right size, is of such probable structure, as referenced to in said application.
If the difference appears drastic enough, I thank this argument is a good one.
However, the prospect of this application does not appear very good.
The demonstration at Bergmann's on the 12th went off successfully, although it did not require little work to determine the conditions made which Mr Pollack [electrode?] is the least active. It, for instance, finally divided from is employed for the preparation of the electrode, and if the hearing, prescribed by the Pollack specification, is carried out at a too high temperature, there is formed an iron scale of such quality that an ordinary size electrode (5 grams) may give as much as .4 amps hour.
The examiner declared finally willing to grant the [illegible] iron patents, but before doing so he demands proved, 1) that the Pollack electrode does not improve materially by forming [by?] current", and 2) that the Edison "electrode does not deteriorate during such treatment, i. e. in the course of 20-30 charges and discharges. I have nearly finished the experiment to prove these facts, and I hope to be able to [illegibe] the result filled within Sept 30th.
The plating of magnesium also succeeded [granite?] [well?], and the examiner has promised to grant this patent as well.

We applied some time ago for a conference with the "Board of Examiners" for the purpose of explaining the demand of a [illegible] by some German authority, and in order to argue for the "combination" patent in general This conference was held yesterday. After persistent argumentations from an [aide?], the Board decided to grant a claim of the following wording:
"Electric accumulator, with interchangeable "alkaline electrolyte, the depolarizer of which contains a nickel [illegible], and the other electrode of which contains a metallic oxide practically insoluble in the electrolyte, characterized thereby, that in the change state of the accelerator, the active part of the negative pole-electrode consists of fewer axles of Iron, or of metallic iron or of a mixture of both."
The claim has been changed considerably, partially by [his?] and partially by the Board. However, I think it is as broad as can be, leaving no way of going around, and saying nothing of the processes that [occur?] in the main electrode.
Under the [illegible] [illegible] oxide of iron, "in the German language" to be understood as one examiner expressed himself (when asked): any iron oxide capable of further oxidation"
Furthermore, the claim appears strong and tenable. The claim will be granted on the condition, that a comparative test of the Edison battery and [illegible], practical lead battery [turns?] [out?] to the decided favor of the [forms?]. For this purpose I shall tomorrow take the test battery, still in my possession, to Professor Forster in Dresden, who will then make the test referred to.
Having received no address to the contrary I intend to leave for New York on Sept 30.
I am very glad to be able to give as good news as the before I leave Europe.
- Messrs Brandon Brothers, Paris [illegible] me as follows:
We take the liberty of expressing the opinion "that it will be absolutely necessary for you to proceed to Budapest in order to meet the opposition caused by Jungner to the Hungarian patents [illegible]"
I therefore think it advisable, although I have not yet received orders, to go down to Budapest and tomorrow, to look over the case and render the assistance I can.
Yours respectfully
Rob. Rafn
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