344 Dewey on Geology of Williamstown, &c. 
At the north end of Saddle Mountain, but low down, yellow 
earth is connected with reddle, or a substance much resembling 
it. It is less hard than the common reddle, but is composed 
of the same ingredients j 
Magnetic ee, Iron, regular octahedrons, in mica slate at 
the base of Stone Hill. 
Supersulphuret of Iron, massive and crystallized, in argilla- 
ceous slate, mica slate, compact limestone, and quartz. 
17. Prase. Beautiful, and containing sulphuret of Iron; 
lately found by Mr. Eaton, a little east of the summit of Hoo- 
sack Mountain, in Florida. 
18. Puddingstone. Where Pownal Mountain reaches the 
Hoosack, (T) 3 miles north of the college, are some hills of 
this aggregate. It is composed of rounded masses of quartz, 
chlorite and limestone, of various sizes, connected by an ar- 
gillaceous cement. : 
19. Potters’ clay. Excellent for vessels of common pottery. 
The minerals of this section, it is obvious, are not very im- 
portant; but as connected with a transverse section of the 
country, they possess considerable interest. For this reason 
they have been particularly mentioned. 
In the north part of Williamstown is a mineral spring, famil- 
iarly called the Sand Spring (S.) The water rises from seve- 
ral places in a reservoir of about a rod in diameter, and from 
one to three feet deep. It is very soft and warm, but contains 
very little saline or earthy matter. Gas continually rises iM 
it. It appears much to resemble the spring at New Lebanon, 
New York, and has proved useful in the cure particularly of 
some cutaneous diseases. 
The transverse section, connected with the map, passes over 
_Stone Hill, and the north part of Saddle Mountain. The dif- 
ferent rocks are shown in the section, directly below their 
places on the map, by drawing lines from the several strata 
parallel to the sides of the map. This section is connected 
with that given by Mr. Hitchcock, in the second number of this 
Journal. It ought perhaps to be mentioned, that according 
to Mr. Eaton’s account, the granite of this section sinks under 
on 
