264 ICE-MARKS AND ANCIENT GLACIERS 
Mountain, a peak lying just south of Tin Mountain, and 
estimated by Prof. Guyot to be 2,500 feet high. Here 
the grooves are well marked, and point directly towards 
Mount Washington, their course being north 25° west. 
Even portions of a quartz vein which appears upon the 
surface is smoothly polished and finely striated. On re- 
moving the soil from the surface of the rock a part of the 
way up the mountain, and also directly upon the summit, 
these ice-marks could be easily discerned, all running in the 
same north-west and south-east direction. On Mount 
Kearsarge, three miles distant, which bears south 25° east 
from Thorn Mountain, Dr. Jackson states, in the Geology 
of New Hampshire, that part way up the mountain the 
drift-marks run north 35° west,—thus pursuing the gene- 
ral north-west and south-east course the valley here as- 
sumes. In hastily ascending this mountain on the north 
side from Jackson, we were not fortunate enough to dis- 
cover any grooves in the rocks. Half way up the side, 
however, we found a boulder of a peculiar mica slate, 
containing large crystals of staurotide, or cross-stone, 
which must have been borne down on the back of the 
glacier from Mount Washington, as thick beds of this 
rock occur near the limit of trees, a little over four thou- 
sand feet up that mountain. Similar boulders occurred 
on some of the hills below. 
On an adjoining hill near Goodrich’s Falls, are very 
distinct ice-marks. Here we found a huge angular 
boulder of many tons weight, which had been ap- 
parently detached from the parent rock beneath, and 
moved a few rods to the south-east; for to the north- 
west are polished surfaces and grooves which had evi- 
- dently been made by this large, slowly-moving mass of. 
= when frozen, info the bottom of a glacier. The 
o 
