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	River, about 150 miles above its mouth; and after several at­tempts the spot was visited in 1882 by Lieut. G. M. Stoney, U. S. N. "He collected specimens of jade in situ, and a number of samples were examined. They may be described as follows : A. Greenish gray, splintery, lamellar in structure; B, like A, but more granular; C, paler, nearly white, closer grained ; D, brownish, highly foliated. All four were analyzed with the following results:
	The foregoing evidence is sufficient to show the essential identity of all the Alaskan jades, and to dispose of the theory that their presence in Alaska is to be accounted for upon the basis of trade with Siberia. That theory is also negatived by the discovery, announced by George M. Dawson, of small nephrite boulders on the upper part of the Lewis River, not far from the eastern boundary of Alaska. But these nephrites are also strik­ingly like those from many other localities, and two of the latter have been included in our comparisons. First, a water-worn, dark-green boulder from New Zealand, sent to the Museum by Sir Julius Haast; and second, a small implement from Roben-hausen, Lake Pfaffikon, Switzerland, out of the collection of Thomas Wilson. The latter specimen, also green, had a specific gravity of 3*015, as determined by Dr. William Hallock, and a more weighty distinction is based upon the presence of inclosures of foreign matter in the Siberian nephrite, which are quite lack­ing in the specimens from Alaska. True jade or nephrite has not been observed in the United States, although early mineralogists referred the bowenite of