A member of the geological survey says that Salt Lake will be of great value in the near future, not only on account of the common salt it will produce, but also for the sodium sulphate it contains.The latter is separated in a floceu-lent precipitate by the cold weather of -midwinter, and annually thrown up on the shore in Enormous quantities. There are many other lakesjin the far west whence an inexhaustible supply of commercial alkalies may be obtained at Small cost Mono Lake, California, being estimated to hold over 78,000,000 tons of sodium carbonate.