s73 Disscattantes. 
rying from fine grained to coarse grained. It is brittle, but yields 
more easily in one direction, separating into angular parts, resembling 
loaf sugar closely, in some specimens. Color varies from snow-white 
to reddish brown and gray. Some specimens have a lemon yellow 
tint irregularly distributed; specific gravity, 2.290; taste, nitrous, 
with a cooling impression; odor, peculiar, and when warmed resem- 
bling chloride of iodine dissolved in water. 
Composition of average specimens is nitrate of soda 64.98, sul- 
phate of soda 3.00, chloride of sodium 28.69, iodic salts 0.63, shells 
and mar] 2.60,—99.90. 
Mixed with this mineral, I have found nitrate of potash, sulphate 
of lime, chloride of sodium, iodate of potash or soda, and chloriodate 
of magnesia, the latter imparting the bright yellow tint which some 
specimens show. 
April 1, 1840.—Dr. D. H. Srorer, in the chair. 
Dr. Storer presented-the er report on the fishes referred to 
him at the last meeting of the Socie 
The fishes presented to the sisee ‘ad its last meeting, as having 
been taken from Jamaica pond, about five miles from this city, are the 
Osmerus eperlanus, common smelt. You may be surprised at the 
circumstance of salt water fishes being taken in a fresh water pond 
entirely disconnected with the sea. During the preparation of my 
report upon the Fishes of Massachusetts, I learned from Benjamin 
Weld, Esq. of Roxbury, it was generally understood that the smelts 
found in Jamaica pond, were originally placed there by Governor 
Barnard. Investigating this subject, to procure some certain data, I 
met with the following extract, in a note, by Daines Barrington, the 
then Vice President of the Royal Society, toa letter from John Rein- 
hold Foster, ‘ton the management of Carp in Polish Prussia :” 
**T have been informed by Sir Francis Barnard (the late Governor of 
New England) that in a large pool which he rented not far from Bos- 
ton, and which had not thie. least communication with the sea, several 
of these fish, originally introduced from the salt water, had lived many 
years, and were, to all appearance, very healthy. ™*% AsIT have never 
heard of this fish having been taken in any other pond in this neigh- 
borhood, there can be but little doubt that the ‘large pool” referred 
to in the above note, was Jamaica pond.t The specimens you per-_ 
ve are considerably smaller than those purchased in our market— 
| Transactions, Vol. 61, for the yo 1771, 312. 
ained since writing the above, that Gov. aaa s residence was 
amaica 
