[D0014AAK], Letter from John Vincent Miller, Cloyd Mason Chapman to Thomas Alva Edison, July 10th, 1900
https://edisondigital.rutgers.edu/document/D0014AAK
Transcription
Dolores, N. M. July 10, 1900. Thomas A. Edison, Esq., Orange, N. J. Dear Mr. Edison :- Your letter of 2nd inst. was duly received and in reply we would say concerning "the other small streams in the vicinity of the mesa" that there are none except after storms and a few small springs. Water is found in a few shafts near the foot of the mountains above the mesa and in and near Dolores. We will make determinations of the amount of water coming from these springs and shafts. Since our last report we have been taking runs with the separator to determine the more efficient method of screening as mentioned in our report of June 19th. We were delayed a considerable by having to devise a means of improving the evenness of the blast before going ahead with these runs. Although the blast seemed even and quite satisfactory at Orange, the work here at once showed that an improvement in the blast would considerably reduce the concentrate. We have now an arrangement which seems quite satisfactory and has shown good results with three widely different sizes of material - the concentrate having run as low as 1/2% without the loss of any gold of any where near the [illegible text] size of the material used, all gold lost was very fine. So far all the runs that we have assayed have shown a saving of more than 99% of the gold and the concentrate ran not higher than 25% of the total gravel used. We have determined to use a combination of the two methods of sizing - taking out the large sizes first down to about .018" and then starting with the finest screens and going up to the .016". By this method we obtain very much cleaner sizing, cut down the wear on the fine screens and also lessen their number. The reason we change the order at .016" is the difficulty of handling the finest sizes alone. The carpenters are now making the necessary changes in the sizers to adapt them to this method. We are now about ready for the magnetic separator that you intended to send us and hope it can be forwarded soon. Mr. Burn has arranged with a surveyor of Santa Fe to make a contour map of a portion of the mesa. This work will be commenced the latter part of this week or the first of next. Very respectfully yours, John V. Miller - Cloyd M. Chapman.