Page:Architectural Review and American Builders' Journal, Volume 1, 1869.djvu/717

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1839.] Cryolite. 575 stern, the anchorage, though secure, being almost exclusively by making fast to iron rings, set in the granite rocks of the shore. This Soda Ore, as it may popularly be called, is found in juxtaposition with granite, the rock immediately overlying the Cryolite, and forms a quarry, 600 feet in length by 200 in width, extend- ing, from the clip of the stratum under the sea, apparently to an unfathomable depth ; the blocks increasing in richness and purity, as the workmen descend, large quantities quarried at a depth of 80 to 100 feet from the surface, affording by test 99| per cent, of pure Cryolite ; and whole cargoes containing scarcely a trace of any other mineral whatever. This gra.id deposite of Cryolite was first discovered by the Esquimaux — a few years since — at the foot of a granite mountain chain, which, commencing at the water's edge, rises, almost perpendi- cularly, to the height of a thousand feet, and, then receding, forms a plateau, followed again by ridges and other plateaux, until an elevation of from five to ten thousand feet is attained. The Danish Government has granted a concession of this gigantic vein, or mine, for a long term of years, to the " Kry- olith Mine og Handels Selskabet," or " Ktyolite Mining and Trading Society," of Copenhagen ; and, through arrange- ment, with this company, in turn, The Pennsylvania Salt Manufacturing Company are the distributors of this valuable mineral, for all North and South America, importing upwards of six thousand tons per annum. By contract, the Danish Company is not allowed to ship any Cryolite of a quality below 80 per cent. ; and all cargoes lost at sea are settled for, by the Pennsylvania Salt Manufacturing Company, upon that basis. Practi cally, by the American Company's books, the average of all the ship- ments is considerably above 80 per cent., the Danish Company being careful to send none below. The settlements are made from the equation of two search- ing analyses of every cargo, the one by a Danish chemist — representing the Kryolith Mining and Trading Society — sent over to, and residing in, Phila- delphia ; and the other by the chemist of the Pennsylvania Salt Manufac- turing Company, also stationed here. The last named Company is entitled, per fixed scale, to a deduction in price for every unit under an agreed per centage ; and pays an additional sum for every unit above the same. This, though a somewhat protracted, is a very just method of settlement for both sides. It follows, in fact, 'the general mode long pursued with copper ores, guano and other products of varying quality. As our readers may like to know how such an analysis is conducted, we would say : That a large number of pieces taken at random from the cargo, as unshipped in bulk, are coarsely ground. The product — amounting often to a number of tons — is evenly heaped, and divided into four approximately equal heaps, by a right-angled cross separa- tion. The two diagonally opposite heaps are thrown together, ground finer, again heaped, and again divided into four nearly equal heaps, of which, this time, the two other opposite diagonals, by the points of the compass, are taken to form the third heap, which is ground still finer, and again subdivided into four, and still again two oblique quarters taken, and again heaped and again ground, and yet again separated into four, and two other diagonally opposite fourths selected, and so on ; grinding finer and finer, and alternating the two fourths chosen, until the mass of impal- pable powder is brought to quite a small bulk, which is then accurately divided into three equal portions, of which one is sealed up, in the presence of the agents of the parties concerned, for the use of the chemical umpire, if ultimately necessary, one is given to the analysing chemist of the party purchas- ing, and the remaining one to the anal-