In the north part of Williamstown is a mineral spring, familiarly called the Sand Spring (S.) The water rises from several 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 in 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 different 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 2d number of this Journal. It ought perhaps to be mentioned, that according to Mr. Eaton's account, the granite of this section sinks under gneiss to the east, and rises again in Hampshire County, "supporting the same rock of gneiss;" but where it reappears, the granite contains "many imbedded minerals." This section corresponds generally to the place and character of the minerals in any section across Berkshire county. There are, however, some peculiarities which may be mentioned at a future day. The colouring corresponds to that on the geological map in Cleaveland's Mineralogy.
C. DEWEY.
Williams' College, Jan. 27, 1819.
P.S. I have a part of a rock crystal, which contains, in a hollow, a liquid and a little air, and some black or brown particles, which just sink in the liquid. It was found several years since at Diamond Hill in Catskill. This hill is only a small eminence on the bank of the creek at that place, composed of limestone, (if I have been correctly informed,) between the strata of which, and on the side next the creek, this and other rock crystals were found. I believe, Sir, you have one like the above, obtained from the same place. The crystal, which was generously given me by Mr. Van Loon, who found it, is only a part of two crystals connected at their bases. Partly under one of the solid angles formed by the united pyramids, is the hollow, about ⅝ inch long, about ⅜ filled with the air, and about ¼ inch wide. The principal curiosity about it is the liquid. It has never been known to freeze. It was exposed yesterday morning an hour to an atmosphere 4 and 5 degrees below zero. It became less fluid, for the bubble of air moved with less ease and rapidity. Still the liquid was fluid. Its colour, which is naturally white, had a slight tinge of yellow. The Rev. Mr. Schaeffer of New-York supposes the black particles are bitumen. Is it possible the liquid is naptha? This oil is sometimes colourless, and does not congeal at zero, and that which I distilled from the Seneca oil, does congeal at some degrees below zero. It can hardly be salt water, unless it be very salt, and even then, it would have congealed at the temperature of the air yesterday. What way can be devised to ascertain what it is?
Jan. 30, 1819.
After seeing the notice of the crystals found at Hudson by Mr. Schaeffer, I wrote to a member of the Lyceum of Natural History, New-York, rather more full an account than the above, of my crystal, &c. I hope to ascertain, whether the liquid will congeal at 10 or 20° below 0, but have some fear lest the crystal should be injured.
C. D.