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tained them from the Hawk Mica Mine, four miles east of Bakersville, North Carolina. They were found at a depth of 380 feet, and proved to be a variety of oligoclase, remarkable for its transparency. The clearest piece measured 3×2×1 inches. In color, it is a faint window-glass green, and contains a series of cavities (see figure, natural size), surrounded and fringed by tufts of white needle-shaped microlites;

these measure from 0.5 to 1.5mm in diameter and are quite round, resembling

those occasionally present in the Ceylonese moon-stone.

The wonderful transparency of the oligoclase and the white inclusions gives the whole mass a striking resemblance to the lumps of glass, so commonly obtained from the bottom of a glass pot. It was mistaken for this until the highly perfect cleavage was noticed; this is remarkable for the entire absence of the striæ so characteristic of the plagioclase feldspars.

Recently some material of a slightly different character has been obtained at the mine. Cleavage masses of white striated oligoclase three inches long were found, containing nodules about 10 to 15mm square: these are as colorless and pellucid as the finest phenacite and are entirely free from the inclusions found in the greenish variety. This transparent variety like the other shows no striæ.

The following analysis was very kindly furnished me by Professor F. W. Clarke. It was made from the faint green variety and shows it to be a typical oligoclase. The specific gravity I determined to be 2·651:

4. Apatite from near Yonkers, N. Y.

I recently received from Miss F. R. M. Hitchcock, a fragment of an apatite crystal, which was found in the spring of 1887, in the tunneling at shaft 16, new Croton Aqueduct, Yonkers, Westchester County, N. Y. It is 10 by 15mm, and is

merely a fragment perhaps of a crystal several inches in diameter. It is of a rich oily green, absolutely transparent and for perfection and transparency equal to anything ever found at the Knappenwand, Untersultzbachthal, Tyrol. Associated with the apatite was a granular epidote on which were some small dark green crystals of the same mineral.

5. Cyanite from North Carolina.

Mr. D. A. Bowman, of Bakersville, North Carolina, has kindly called my attention to some minerals from Bakersville, one of the most interesting of which is cyanite in distinct isolated crystals that for perfection, depth of color and transparency rival those from St. Gothard, Switzerland. They are found at an altitude of 5500 feet near the summit of Yellow Mountain, on the road to Marion, N. C., four miles southeast of Bakersville. They occur in a vein of white massive quartz in a granitic bluff, associated with almandite garnet of a very light pinkish purple color, but not transparent. The vein has a dip of 60° bearing N.E. and S.W. The color varies from almost colorless to deep azure blue, as dark as the Ceylonese sapphire. Some of the crystals were two inches long while a few were observed 15mm in width, and 10mm in thickness. No terminal planes were observed. Occurring in white quartz, they form beautiful specimens and the loose crystals were extensively sold for sapphire at Roan Mountain, the tourists'

resort.

6. Aragonite Pseudomorph.

Among a collection of minerals sent to the Arizona Exhibition at New Orleans from Pima County, Arizona, was a crys

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tal originally aragonite, which had been almost entirely changed and impregnated by oxide of manganese. and red oxide of iron. It has an outer coating of white cacholong over some simple rhombohedral crystals, now entirely changed to an oxide of manganese. The crystal is hollow on top to the depth of three-fourths of an inch. The sides of the cavity are lined with cacholong, but the bottom of the cavity is partly filled in with a white compact chalcedony. The figure shows the crystal in natural size. The interior of the crystal is radiated, but is of a dark chocolate color and almost entirely altered to hematite.

SCIENTIFIC INTELLIGENCE.

00. Explorations of the Gulf Stream, by Lieut. J. E. PillsBURY, U. S. N.-The Report for 1886 of the U. S. Coast and Geodetic Survey contains, in Appendix No. 11, a Report of new Explorations of the Gulf Stream, illustrated with maps, which closes with the following conclusions (p. 289):

"I have to submit the following summary of my conclusions, based upon the information obtained during the two seasons' observations. The examination of the Gulf Stream currents having been made in March, April, May, and June, the conclusions may be incorrect for other seasons of the year, although there are no good reasons for supposing that such is the case except, possibly, in the amount of the variations.

(1) Between Fowey Rocks, Florida, and Gun Cay, Bahamas, the current varies daily in velocity, at times as much as 24 knots. The greatest velocity is generally about nine hours before the upper transit of the moon. The variations are most excessive on the west side of the straits and least on the east side.

(2) The average daily currents vary during the month, the strongest set coming a day or two after the greatest declination

of the moon.

(3) The axis of the Gulf Stream, or the position of the strongest surface flow in passing this point, is 11 miles east of Fowey Rocks Light-House. The strongest surface current found here was 54 knots per hour; the least, 1 knots; and the average, 3 knots. The average current at other places on either side of the axis is as follows:

(4) The wind probably retards or accelerates the velocity of the current. A northeast gale in the Atlantic will probably "break up" the water of the stream, lowering its velocity materially, and afterwards the flow will, by the reaction, be greatly increased over the normal speed. There is no evidence of any change in position of the axis of the stream due to the wind.

(5) Two days' observations off Jupiter Light, Florida, indicate the same daily variation as was found off Fowey Rocks, and the axis of the stream at this section is probably about 17 miles east of the light."

Appendix No. 12, in the same report, is a new and greatly enlarged review of the "Secular variation of the magnetic declination in the United States and some foreign Stations, by Charles A. Schott. It covers pages 291 to 407.

OBITUARY.

HENRY CARVILL LEWIS.-Professor Lewis, of Philadelphia, died at Manchester, England, on the 21st of July in his thirtyfifth year. He was a graduate of the University of Pennsylvania, an active member of the Academy of Sciences of Philadelphia, and in 1883 became Professor of Geology in Haverford College. One of his earliest papers, if not the first, is a notice of the Zodiacal Light, giving the results of five years' observations; it was read before the American Association in 1880, and appeared in vol. xx (1880) of this Journal. He commenced his glacial investigations in 1879, in connection with the Geological Survey of Pennsylvania, worked on the same subject in 1885 and 1886 in Great Britain, and had intended to make observations the present season in Norway. The investigation of the "Terminal Moraine" from the eastern boundary of Pennsylvania (to which point it had been traced across New Jersey, by Professor G. H. Cooke), westward across Pennsylyvania, occupied him until the autumn of 1882, when his report of about 300 pages was presented for publication. It appeared in 1884, as No. Z of the Geological Series of the Pennsylvania Survey. In 1886 he read his paper on Glaciation in Great Britain before the British Association.

Professor Lewis was also a zealous mineralogist, and until recently had editorial charge of the mineralogical department of the American Naturalist. In 1886 he brought out his paper on the "Genesis of the Diamond," tracing it to eruptive rocks, and basing his views principally on the published accounts of the diamond fields of Southern Africa.

Mr. Lewis was an enthusiastic and energetic worker in Science, and promised to do much for its progress. He leaves a wife and one child.

JAMES STEVENSON.-Col. Stevenson died on the 25th of July. He was born in 1840, at Maysville, Kentucky. He was an early explorer of the Rocky Mountain region, and accompanied Dr. Hayden in his expedition as executive officer and manager. In 1872 he ascended the highest of the Teton Range, the Great Teton. He has been, since 1879, connected with the U. S. Geological Survey, engaged in making ethnological investigations and collections in New Mexico and Arizona. A very valuable report by him on the collections obtained in 1879 and 1880 is contained in the Report of the Secretary of the Smithsonian Institution for

1881.

ALBERT D. HAGER.—Mr. Hager was associated with Professor Edward Hitchcock and Mr. C. H. Hitchcock in the Geological Survey of Vermont. Since 1872 he has lived in Chicago, where he died on the 29th of July. He was born at Chester, Vermont, in 1817.