346 Mineralogy of Jefferson and St. Lawrence Counties, JV.Y. 



the water. The addition of a few drops of a solution of sulphate of 

 copper to the fluid, strikes a blue color. instantly, thus denoting the 

 presence of ammonia. On examining the residuary matter in the 

 retort, it is found to be strong sulphuric acid. I know of no other 

 rationale of this process, and think it quite satisfactory. Of one 

 thing, however, I am certain, and that is, that no other method that I 

 have employed, yields the gas in question, so pure, and with so little 

 trouble. It is, therefore, confidently recommended to all operators in 

 chemistry. 



Cincinnati, October 22, 1833. 



Aet. XI. — £ Sketch of the Mineralogy of a portion of Jefferson 

 and St. Lawrence Counties, (JV. Y.) ; byDrs. J. B. Crawe, of 

 Watertown, and A. Gray, of Utica, (N. Y.) 



The northern part of the state of New York, has for a long time 

 been known to contain many interesting minerals. But with the ex- 

 ception of diat portion which borders on Lake Champlain, this region 

 has not received that notice from our mineralogists which its importance 

 seems to deserve. In the spring of the present year, we visited this 

 region for the purpose of collecting minerals, and had the good for- 

 tune to discover some interesting localities, a brief notice of which 

 may not be unacceptable to the readers of the American Journal of 

 Science. 



• The underlying rock at Watertown, Sackett's harbor, and through- 

 out nearly the whole of Jefferson Co. is the metalliferous limestone 

 of Eaton. This rock contains fev/ minerals, but abounds in interest- 

 ino- organic remains. Orthoceratites, two to three feet in length are 

 extremely common near Watertown and Brov^nville. Ammonites^ 

 Madreporites, Turboniles, &c. occur in great abundance. Two 

 Trilobites, the Cahjmene Blumenbachii and the Isotelus gigas of De- 

 kay, have been found near Watertown, but they are by no means 

 common. In general this rock in Jefferson Co. contains the same 

 petrifactions as at Trenton Falls on the West Canada Creek. 



The Lenticular Carbonate of Lime is found in this rock at Broivn- 

 ville, four miles from Watertown. A single specimen of Sulphate 

 of Strontian in slender crystals, was found on the same locality. 

 On the shore of Lake Ontario, a few miles N. E. of Sackett's har- 

 bor, at a place called Pillar Point, is a locality of Sulphate of Barytes. 



