486 
GEOLOGY OF THE FIRST DISTRICT. 
the point of former fluidity, as on account of ready access on a public road by which the 
stages pass daily. Here are also rounded grains of quartz, and scales of plumbago*" are 
seen with augite and other minerals. Numerous localities might be referred to. They are 
indicated on the geological map of the county. There are many in Putnam and Fort-Ann. 
Some of the limestone beds have been mentioned as evidently injected, or at least have been 
fluid, or partially so. Prof. L. C. Beck found white limestone, that undoubtedly belongs to 
the metamorphic rocks in Washington county, in Fort-Ann. 
“ At Shelving rock, about twelve or thirteen miles north of Caldwell, a belt of white lime¬ 
stone stretches through the granitic or mountain rocks. In this, nodules of serpentine were 
found, with fine fibres of amianthus running through them in various directions. In another 
part of the same bed, the variety of this mineral called steatite occurs ; as also tremolite, a 
common associate of the above, in small quantity. A similar belt of white and very crystal¬ 
line limestone was observed about three and a half miles south of Shelving rock, on ihe farm 
of Mr. Samuel Phelps, in the town of Fort-Ann, Washington county. Here we also noticed 
dark colored serpentine, pyroxene and common garenet, but the specimens were too imper¬ 
fect for cabinet exhibition.”! 
There are other beds of this limestone that I have scarce a doubt are metamorphic rocks, 
once beds of the Mohawk limestone, now altered rocks, partaking of the character of primary 
rocks, and interstratificd at high angles of inclination with gneissoid and granitic rocks. 
Examples may be seen north of Fort-Ann, along the western side of the spur of mountains 
that lies between Wood creek and the valley that leads to South bay of Lake Champlain. 
The white limestone and granite were seen in contact in large beds, and the grey and blue 
limestones of the Champlain division (the Calciferous sandstone and Mohawk limestone), 
within a few rods, where they had been but partially uplifted, but not brought in contact with 
the granitic rocks. 
Beds of the white crystalline limestone were observed in many places on the tract of moun¬ 
tains in Fort-Ann, between Lake George and the valley leading from Fort-Ann to South bay 
of Lake Champlain, and various others were mentioned to me in Putnam, similar in character, 
which I did not examine. 
The white limestone is frequently mixed with mica, augite, etc., like that of the Highlands 
and Warwick, and it has undoubtedly the same origin. In the Warwick valley, the limestone 
can he easily traced through all the changes from a fossiliferous, to a crystallized v)hite 
limestone, containing crystallized minerals and plumbago. In the Highlands and in Wash¬ 
ington 'county, the limestone is the same in character, containing the same minerals, and 
associated with the same rocks, apparently exhibiting a still higher degree of change, but 
rarely giving any evidences that can be definitely adduced as showing the gradual change 
from the fossiliferous to the crystallized limestones. The evidence that we can adduce, is, 
• A small vein of plumbago was pointed out to me by the proprietor, near this mass of limestone; but it is too thin to be of any 
t Prof. Beck, Fifth Annual Geological Report of New-Yoik, p. 14. 
