Central City Colorado Collom's Ore Washing Machine Mining Rare Engraving 1870

This steel engraving print is out of a very rare book, Report of the Geological Exploration of the Fortieth Parallel. Clarence King Geologist, Volume III, Mining Industry by James D. Hague. Government Printing Office 1870.

The best example of a failed innovator is that of Devonshireman John Collom. He came to Colorado in 1865 via Lake Superior, Michigan, and was early to the silver strikes. he invented an improved concentrating machine at Lake Superior, the Collom jig, which was nearly universally accepted in that copper-mining country. While continuing to improve l,js jig and an ore-washing machine, he designed a series of milling and smelting plants near Georgetown. In 1880, he was still in the county, trying without success to invent the perfect concentrating machine for the district's ores. One wonders about the Boston investors who continued to back his many failed enterprises. The Ingenious Community: Georgetown, Colorado, and the Evolution of Western American Silver Milling and Metallurgy, 1864-1896. By Robert L. Spude. 

The drawings on Plate XXXVII show some of the details of the construction of John Collom's design.. The concentrating machinery, used for the preliminary dressing of the ore, as a preparation for smelting, comprises two Dodge crushers, a series of Cornish rollers, screens or appliances for sizing the material, and four of Collom's ore-washing machines. The last-named apparatus has been proved by long experience, not only in the district referred to in these pages, but elsewhere in our mining regions, as a most useful and efficient ore dresser. As it is believed to be a machine that may be advantageously introduced into some of our western mining districts in which concentration is yet to become an important feature in the manipulation of ores,” Report of the Geological Exploration of the Fortieth Parallel, Page 621.

Size of sheet is overall length 9" X 11 1/2" wide, image 6" X 8 1/2".

Condition: Crisp and clean. Once framed this map will be an excellent example of a historic print that is 132 years old.

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