Mineralogy and Geology. 429 
ee angela of iron. Rossie and Governeur, in iron mines. Fowler, 
anto 
ap i of copper and iron. Canton, Fowler, Macomb, &c. 
Tourmaline. Rossie, Governeur, Hermon, &c. Often of a brown 
and yellow color. 
Tremolite. Governeur, in splendid crystalline and fibrous masses 
b. 
Zir Hammond and Rossie. Coarse opake specimens may be 
Sbiained with facility. Beautifully crystatlined and very perfect speci- 
Mens often procured. It occurs in primary limestone, associated with 
apatite, feldspar, loxoclase (?) hyalite, graphite, &c. The pr cipal 
ocality is on the farm of Mr. Hardy. It has been improperly attribu- 
0 the farm of Mr. Robinson. 
Isomorphism of Miargyrite and Augite. —Miargyrite crystalizzes 
Augite has M: M==87° 6’, P: M=100° 25’. 
fhe augite group of isomorphs with this addition includes, augite, 
yroxene, glauber salt, acmite, hornblende and miargyrite.* Calcula- 
ng the atomic volume of miargyr - we have 
A = 3762'8 — 5-234 (sp. gr.) =718 C= 7189 —6=1198. « 
The result 119-8 divided by 24, ne va rs which is very near the 
atomic volume of the augite series. If antimony is taken as a double 
atom, it gives 718°9-—-7—102-7, which is a tle more than double 
number for the augite series. Moreover, the whole number 718°9 i 
not much above the number for Hudsonite. We repeat the snthets 
here for comparison. 
A. B. 0. 
Pyroxene, Ist var, (Ca, Mg) 3 §i2 637° 127-4 45°5 
2nd var. (Oa,Mg, Fe)? Si2 645-2 129° 46:1 
var., Hedenbergite, 6734 1384°7 481 
4th var. Fes Si2 6747 185 48-2 
5th var, Mn3 Si2 6848 1369 48°9 
6th var, « Hoientia, 1060 1412 489 
iy - : - 718°9 119°8 (or 1027) 
Acmi . . 9185 1837 48°34 
Ba 3 Ist var. - 9716: 1388 48°58 
nd var., a, alumiow, - 15595 47-25 
3d . 138'4 48:48 
ngs var. . 144-0 48°24 
Borax, f . 13916 1070 638 
Glauber alt. 12905 10754 496 3D. D 
nalysis of the Sclorlomite Ag Sp tele ; by C. Rammetspere, 
(Poggendorf's Annalen, Ixxvii, 1 849). —Rammelsberg finds this 
Ark 
mineral from ansas to cons bag Bi 
. i d Li Protoxyd of iron. Magnesia. 
1, 36-09 ae rr a9 22-83 155 9845 
2. 27:85 15°32 32°01 23°75 152 = 10045 
The results give the formula 
oks Si2+3k2 Ti 
In the 2nd analysis some titanic acid still remained with the silica. 
a Oc 
* See pages 223, 228, 280, of this volume. 
