The Thomas A. Edison Papers Digital Edition

Transcription

Berlin. Sept 20. 1902.
c/o Dr. L. Sell. Dorotheenstr. 22.

Thos. A. Edison Esq
Orange N. J.



Dear Sir:

On the 8th of this month I called you as follows: "Send without fail by first mail sample tested graphite".
The purpose is to show in support of the graphite application, the difference between such treated graphite and some samples of native graphite procured here in Berlin, and, consequently, that it does not follow as a matter of course, that any native 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 think 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 the Pollack electrode is the least active. If, for instance, finely divided Iron is employed for the preparation of the electrode, and if the heating, 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 himself willing to grant the two 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 have the result filed within Sept 30th.
The plating of magnesium also succeeded quite 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 "Gutachten" by some German authority, and in order to argue for the "combination" patent in general This conference was held yesterday. After persistent argumentations from our side, the Board decided to grant a claim of the following wording:
"Electric accumulator, with interchangeable alkaline electrolyte, the depolarizer of which contains a nickel oxygen compound, and the other electrode of which contains a metallic oxide practically insoluble in the electrolyte, characterized thereby, that in the charged state of the accumulator, the active part of the negative pole-electrode consists of lower oxides of Iron, or of metallic iron or of a mixture of both."
The claim has been changed considerably, partially by  us 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 term "lower oxide of iron" is 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 modern, practical lead battery turns out to the decided favor of the former. 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 orders 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 above before I leave Europe. - Messrs Brandon Brothers, Paris write 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 &c."
I therefore think it advisable, although I have not yet received orders, to go down to Budapest tomorrow, to look over the case and render the assistance I can.

Yours respectfully
Rob. Rafn