256 C. U. Shepard on Aquacreptite. 
Art. XXVI.—On Aquacreptite, a new mineral, and on (o- 
rundophilite of Chester; by CHARLES UpHam Suzparp, 
water, was sent me last autumn by Mr. W. W, Jefferis, of 
West Chester, Pa., with the remark that it was found at 
place in a narrow seam in serpentine. The specimens are in 
mite from Miemo in Tuscany. Whether the mineral is at 
original compound, or an oxydated hydration of another sub- 
stance, and if so, of what species, it is difficult to say. At 
present, however, it is entirely homogeneous in aspect, and pos 
sessed of much uniformity of composition. It possesses the 
following characters : 
Massive, H.=2:5. Gr.=2-08 (Shep.), 2:05 (Eaton). Color 
yellowish brown. Streak orange yellow. Dull. Brittle. Fracture 
small conchoidal. Adheres rather feebly to the tongue. Falls 
asunder in water with a crackling (decrepitating) noise. ie 
decrepitation lasts only for a moment, and is more striking 
the water is warm. It does not wholly fall to powder in watet, 
a portion of the mass still retains a feeble degree of 0 
esion, | 
Ignited in powder, it loses 23 p. ¢. without change of color 
‘ Frevious to ignition it is taken up by aqua regia, with 
tion of the silica, which separates in flocks. a 
Three analyses were made ; 1, by Prof. James H. Eaton ; 
Beloit College, Wisconsin ; 2, by Mr, Henry C. Humphrey, 
student of Amherst College, and the third by myself. 
3 
4. : 
ee 43°03 41°56 41°0 q 
Magnesia,...._____ 19°58 (not determined) 17°60 q 
Peroxyd iron, _.____ 12°30 12°45 13°30 q 
ea Op ea 556 6°71 4°00 b 
yee 17°40 16°00 sedi! 4 
97°87 nil 3 
_ L. Corundophitite—As there had existed some perpen 4 
in reference to this mineral as found at Chester, Mass., ne the | 
cr? associate of the emery and a constituent also ° Pi 
alcose slates embrac ery vein, I requeste® : 
Eaton (then in charge of — dairies College laboratory) a 
analyze the two leading varieties of the corundophilite, phire = 
(1) that in crystals accompanied by diaspore, rutile and sap q 
= saeeR ge 
a8 Saree 
