No. SOO.] 
;269 
at right angles to the adit. The gypsum being very different in its ap- 
pearance from the lake plaster, Mr. Crill, when I first visited the adit 
in the spring, was doubtful of its nature and its quality. Having satisfied 
him on both points, and advising the search for more at right angles to 
the adit, I found, on a re-visit in the fall, that from 20 to 30 tons had 
been obtained. 
The gypsum is very white, and is equal to the Nova-Scotia, both be- 
fore and after calcination. I mention the latter circumstance in conse- 
quence of Mr. C. informing me that he had been told that it became 
yellow by heat, which I did not believe, and which experiment, for the 
information of those concerned, shows to be false. Those who have a 
knowledge of gypsum well know, that in a crystalline state, it has lit- 
tle tendency to mix, much less to unite chemically with colouring mat- 
ter. 
Amongst the products thrown out with the gypsum, were white and 
greenish sandstone, white sand, and the same kind of drab-coloured, 
indurated marl or shale, which encloses the gypsum of the outlet of 
Seneca lake, likewise enveloping small roundish or irregular masses of 
gypsum. Besides these lining the cavities in the sandstone, were crys- 
tals, probably of sulphate of strontian, of a whitish colour, and the same 
in their fibrous plates, of a blueish green colour, lying between the layers 
of the rock. Considerable deposit of hydrate of iron colours the wa- 
ter of the adit when agitated. Of the fossils discovered, they were such 
as characterized the group to which the sandstone belongs, but of a 
lower level. 
The adit was dug in the side of a hill. The upper part of it, where 
other small excavations had been made, exhibited thin layers of impure 
water lime. Near the mine to the west of Mr. CrilPs, there is a conside- 
rable deposit of tufa, much of it stained with yellow oxide of iron. 
The origin of the search for silver, which caused an adit of 430 feet in 
length to be excavated, and at a cost of about $3,000, is no bad ex- 
emplification of mining operations, commenced without appropriate or 
requisite knowledge. The ochery stainings of the calcareous tufa, the 
ferruginous waters, and above all the divining rod, first prompted to the 
working. With these fallible guides, another plausible one was soon 
added, the excavation furnishing from time to time a number of small 
cavities lined with crystals of sulphate of strontian. Such is the con- 
nection of metallic substances or ores with earthy or saline crystalline 
minerals, as mentioned in the first report, that the latter are known 
amongst miners by the familiar name of blossoms, supposing that the 
