338 J. DeLaski on Glacial Action about Penobscot Bay. 
two hundred feet, and stretches in the east and west direction 
for more than three miles. 
Wherever the formation is of syenite—and there are about 
seventy-five square miles of surface covered with this rock, in 
Vinalhaven—the hills are broken down on their southern brows 
into step-like descents. There is one hill of this character in the 
town from twenty-five to fifty feet high and two thousand broad, 
nearly wedge-shaped, with its apex turned toward: the north. 
I found, wherever I examined them, that the striz had com- 
menced to form at the southern foot of these hills, in straight 
parallel lines, generally very close up to the wall; and, in one 
g and shaded 
ing a little more than one hundred feet directly from the water. 
The formation here is trap. This hill may extend, east and 
