564 
FACTS AND OBSERVATIONS. 
phate, which is more fertilising than Peruvian guano, can be 
sold at Charleston for six dollars a ton; and for facilitating its 
sale, the proprietors have resolved to excavate a canal two 
miles in length, fifty feet wide, and three deep ; w 7 hich, start- 
ing from the deposit of phosphate, falls into the river Arkely, 
w r hich passes the town of Charleston. — Ibid . 
Deposit of Sulphur. — Several of these deposits have 
been discovered in California, where, in one establishment, 
some ten tons are now refined daily. The most recent report 
is from the Suez Canal, w here, on the shores of the Red Sea, 
at the entrance of the Gulf of Suez, two inexhaustible depo- 
sits have been found. One at Djemsah, is situated in a per- 
fectly rainless desert on the African coast, very near the sea, 
and consists of a hill 600 feet high, composed entirely of 
sulphur. In order to obtain the sulphur, it is blasted like 
the rock in a common stone quarry. Two hundred Arab 
labourers are occupied, under the supervision of French 
engineers, and produce some ten tons of sulphur a day. A 
railway is in course of construction, for the purpose of trans- 
porting the sulphur rapidly and in large quantities to the 
furnaces in which it is refined, and thence to the coast to be 
shipped. The Viceroy of Egypt buys from the French com- 
pany all the sulphur at eighteen dollars per ton. The other 
locality is Ranga, 500 miles from Suez, and also near the 
coast of the African continent. In this case also the sulphur 
appears in the form of rocks, much purer than the former, of 
a bright lemon-yellow colour, but covered under the earth, so 
that it must be obtained by tunneling. This sulphur mine 
has not yet been w 7 orked to any extent. — Ibid . 
Rock Salt in Prussia. — In Sperenberg, near Berlin, 
borings for rock salt have been carried on for the last two 
years. In February a depth of 2725 ft. had been reached, 
and the thickness of the salt bed explored to 2439 ft. — 
Ibid., April 22nd. 
Test for Arsenic. — Bettendorf has discovered a test so 
delicate that it is said to be capable of detecting one part of 
arsenic in a million parts of solution, nor does the presence 
of antimony affect it. The arsenious liquid is mixed with 
hydrochloric acid until fumes appear; chloride of tin is then 
added, which produces a basic precipitate, containing the 
greater part of the arsenic as metal, mixed with oxide of tin. 
—Ibid. 
