78 CA, Goessmann on the Chemistry of Common Salt. 
Lozoon Canadense. In this connection it should be said that 
the crystalline rocks of Newburyport and Salisbury, though 
separated in Hitchcock's geological map from the gneisses to the 
southwest, and united to the syenites of Gloucester and Rock- 
port, seem to me unlike the latter, and closely related 
lithologically to the gneiss of Chelmsford, which encloses the 
crystalline limestone. The crystalline limestones occurring 
with gneissic rocks near Providence, Rhode Island, merit a 
careful examination for Hozoon, inasmuch as from their litho- 
logical characters they may with probability be supposed to be 
of Laurentian age. 
Montreal, Dec. 13, 1869. 
Art. XI.—Contributions to the Chemistry of Common Salt: with 
particular reference to our home resources ;* by C. A. GOESS- 
MANN, Ph.D., Professor of Chemistry, Massachusetts Agri- 
cultural College, Amherst. 
However chemists and geologists may differ in regard to 
the methods by .which chlorid of sodium has accumulated in 
the course of time within the waters of the ocean, there is at 
present but little dissent from the opinion, that the ocean has 
at all times been charged with salt, and that the saline residues 
of the oceanic waters of former geological periods, together 
‘sh ; 
quantity of the impurities, so far as the same kind of saline 
compounds is concerned, are determined not only by the con- 
dition of the source, but also by the mode of manufacture and 
y the amount of care bestowed upon the working. The fitness 
of a salt for domestic and industrial purposes depends quite fre- 
cial solutions exerts a most decided influence on both, it seems 
but proper that I should briefly consider the chief foreign saline 
compounds usually associated with the chlorid of sodium. To 
dotiia: we must go back to the primitive condition of our planet. 
\ccepting the theory that our earth has gradually passed 
2 * Read before the National Academy of Science at its Northampton meeting’ 
