[LB028814], Letter from Thomas Alva Edison to James Dredge, March 25th, 1889


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[LB028814], Letter from Thomas Alva Edison to James Dredge, March 25th, 1889

Editor's Notes

I have received your letter of 16th instant and have examined the samples enclosed of the first running which you made with the Ore Milling machine. This separation, compared with the results which we obtain here, is a very poor one. There are a great many points about the Ore Milling process which require the attention of a man thoroughly familiar with its operation. The height of the magnet, the position of the hopper, and the strength of the current all have to be adjusted to the requirements of different kinds of ores; and while it is an easy matter for an expert to make those adjustments and to instruct others how to make them, it is a very laborious work for anyone who has not been educated in this particular branch. When the machine is once set for any class of ore, it remains constant. I sent Mr. Wiley an engineer for the purpose of having him attend to these points. If you want to go ahead now and try and run the machine without the assistance of a trained man, you would simply be going over all the work and encountering all the obstacles which I met with and overcame during the early stages of my experiments here. It is thus impracticable for you to operate successfully the installation which you have, and as the recent unfortunate developments, with which you are familiar, have changed my plans, I wrote you a few days ago regarding the disposition that I desired you to make of the Ore Milling machinery. Yours very truly [signed] TAE





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