102 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
Talc is found in twenty sections as small colorless plates. These 
are often scattered throughout the whole section. Where talc is 
very abundant the rock is more properly classed as steatite. 
Cubes of pyrite are present in fourteen sections, but never are more 
than two or three small crystals found in the same section. The 
minerals surrounding it are usually stained by its partial alteration 
to limonite. 
Analyses. 
The following analyses give the composition of the Vermont serpen- 
tine, and show how it compares with that from Georgia and Quebec. 
For No. 1, my thanks are due to Mr. R. E. Somers. 
No. 1. Serpentine from Dover, Vermont. 
No. 2. Serpentine from Belvidere Mountain, Vermont. Analysis 
from V. F. Marsters (3). 
No. 3. Same as No. 2. 
No. 4. Serpentine from Corundum Hill, Georgia. P'rom Pratt and 
Lewis (7). 
No. 5. Serpentine from Thetford, Quebec. From F. Cirkel (8). 
12 3 4 5 
SiOa 38.10 40.21 40.82 41.90 40.76 
AI2O3 2.31 \ , 5 „ 0.71 
FesOa 2.70 \'^' {' 0.91 3.05 
FeO 3.48 0.49 
MnO 0.11 
MgO 42.04 40.98 38.40 40.16 42.32 
K2O 0.15 
NaaO 0.19 
CaO 0.82 1.37 0.35 
H2O 11.45 12.68 12.41 16.16 13.60 
NiO 0.10 
Total 100.53 100.42 100.67 99.94 100.57 
The Vermont serpentine, as is seen from these analyses, is fairly 
uniform. The Dover rock is slightly lower in silica and higher in 
magnesia than that from the northern part. The latter, moreover, 
contains a small amount of lime not found in the southern occurrence. 
If compared with that from Georgia, the Vermont rock is seen to 
contain more alumina and iron oxide, but less water. The Canadian 
