366 T. 8S. Hunt on Salts from Sea-water. 
a large amount of salt, and thus protect them from the atmos-_ 
pheric waters. 
We may mention here a process which, although unknown in 
France, is applied in Russia and on the borders of the White 
Sea, and may, perhaps, be advantageously employed on our own 
shores. It consists in applying the cold of winter to the concen- 
tration of the sea-water. At a low temperature a large quan- 
tity of ice separates, but all the saline matters rest in the liquid 
portions, so that by separating the ice a concentrated brine is 
obtained, which may afterwards be evaporated by the summer's 
sun or by artificial heat. 
Treatment of the Bittern or Mother Liquor.—The waters, which 
have reached a density of 32° in the salting tables, have already 
deposited the greater part of their common salt, and now con- 
tain a large amount of sulphate and hydrochlorate of magnesia, 
sea with a portion of chlorid of potassium. The admirable 
researches of Mr. Balard have taught us to extract from these 
mother liquors, sulphate of soda, and salts of magnesia and pot- 
ash, so that although formerly rejected as worthless, these liquors 
are now almost as valuable as the salt of which they are the 
residue 7 
that by taking advantage of this decomposition, the sulp 
soda can be advantageously prepared from t 
salting tables. *. heat 
When the liquors of 82° are evaporated by the pores se 
* 
