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Document Max. Freq Min. Freq
Harper's Encyclopedia of United States History (ed. Benson Lossing) 3 3 Browse Search
Medford Historical Society Papers, Volume 13. 3 3 Browse Search
Knight's Mechanical Encyclopedia (ed. Knight) 2 2 Browse Search
Edward L. Pierce, Memoir and letters of Charles Sumner: volume 4 2 2 Browse Search
Lucius R. Paige, History of Cambridge, Massachusetts, 1630-1877, with a genealogical register 1 1 Browse Search
Southern Historical Society Papers, Volume 13. (ed. Reverend J. William Jones) 1 1 Browse Search
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Browsing named entities in Knight's Mechanical Encyclopedia (ed. Knight). You can also browse the collection for January, 1872 AD or search for January, 1872 AD in all documents.

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Knight's Mechanical Encyclopedia (ed. Knight), A. (search)
The number of patents granted in the United States for amalgamators cannot be readily stated, as so many of the crushers, grinders, and arrastras become amalgamators by the addition of mercury. To state the whole number would give an exaggerated view, as many of them are merely mechanical grinders without any specific adaptation to the requirements of the mercurial process. The number of patents for amalgamators in the United States may be approximately stated at two hundred and sixty, January, 1872. With the exception of the argentiferous galena, silver is generally found in the form of brittle sulphides disseminated through the gangue or vein stone. These particles, in the operation of grinding or stamping, are reduced to a fine powder, which floats off in water in the process of concentration. It becomes necessary, therefore, to apply a gathering agent which will collect them, and the notable activity of quicksilver in entering into combination with the precious metals has c
Knight's Mechanical Encyclopedia (ed. Knight), L. (search)
in diameter. The lantern is supported on a cylinder of boiler-iron resting on a platform at the top of the columns. Lighthouse at Trinity shoals. The following is a list of the electric lights in England and France, with the dates at which they were erected: Dungeness, January, 1862; Cape La Heve, France, South Light, December, 1863, North Light, November, 1866; Cape Grisnez, France, February, 1869; Souter Point, England, January, 1871; South Foreland, England, with two lights, January, 1872, in the first place in 1858 – 60 by Professor Holmes, and afterward England took the lead in this matter of the adaptation of electric illumination to lighthouse purposes. The Bishop rock light, Scilly Islands, the old Cassiterides of Herodotus, 145 feet high, cost £ 36,559. In the British Isles there are 357 shore lights and 47 floating lights. The French have 224 shore lights. The average annual expense in England of a shore light is £ 500; of a floating light, £ 1,200. The light