28 
ANALYSES OF EOCKS, U. S. GEOLOGICAL SURVEY. 
[BULL. 168. 
MASSACHUSETTS. 
1. ROCKS OF THE CONNECTICUT VALLEY. 
Described by Emerson in Mon. XXIX. 
A. Serpentine derived from salite, Osburn's soaps tone quarry, 
Blandford. 
B. Dark-green, oily serpentine, center of large Middlefield bed. 
C. Enstatite, slightly altered, from Granville. For comparison 
with D. 
D. Serpentine derived from enstatite, Granville. 
Analyses A, B, and C by W. F. Hillebrand, record No. 1555. Anal- 
ysis D by Geo. Steiger, No. 1536. 
A. 
B. 
c. 
D. 
Si0 2 
ALO, 
40. 77 
1.16 
3.56 
1.47 
39.37 
none 
.14 
.10 
.49 
12.48 
none 
trace 
.28 
.09 
.17 
38.62 
.35 
3.44 
3.99 
40.61 
.40 
.10 
.08 
.36 
10.91 
none 
trace 
.39 
.10 
.21 
54. 04 
.52 
1.51 
3.90 
34. 40 
none 
| .08 
.70 
3.07 
none 
none 
.14 
.11 
.23 
37. 82 
.61 
7.92 
1.15 
37.94 
none 
> trace 
.75 
12. 50 
trace 
trace 
.19 
Fe 2 3 *. 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 Oat 110°.. 
H 2 above 110° 
Ti0 2 
P,Oc 
Cr 2 3 
MnO 
NiO 
.45 
.05 
CoO 
Li 2 
trace 
none 
trace 
.52 
CO., 
1.32 
100. 08 
100. 08 
100. 02 
99.38 
