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Chlorine.—Steam Engines.—Safety-lamp. 
CHLORINE. . 
Dr. Ure of Glasgow has lately finished a very elaborate series 
of experiments on the controversial subject of chlorine. Their 
principal object was to ascertain whether water, or its elements, 
existed in and could be extracted from muriate of ammonia. He 
has perfectly succeeded in obtaining water from the dry and re- 
eently sublimed salt, by methods quite unexceptionable. The 
vapour of such muriate of ammonia being transmitted through 
laminz of pure silver, copper and iron, ignited in glass tubes, 
water and hydrogen were copiously evolved, while the pure metals 
were converted into metallic muriates. This fact is decisive, in 
the Doctor’s opinion, of the great chemical controversy relative to 
chlorine and muriatic acid, and seems clearly to establish the for- 
mer theory of Berthollet and Lavoisier, in opposition to that 
more lately advanced by Sir H. Davy with such apparent cogency 
of argument as to have led almost all the chemists of Europe to 
embrace his opinion. The details of the experiments have been 
communicated some time since to a distinguished member of the 
Royal Society, and will be speedily laid before the public. This 
decomposition of the salt by the metals, at an elevated tempera- 
ture, is analogous to the decomposition of potash in ignited gui- 
barrels, by Gay-Lussac and Thenard. 
STEAM ENGINES IN CORNWALL, 
It appears from Messrs. Lean’s Report, that during the month 
of August 29 engines performed the following work with each 
bushel of coals. 
Water lifted 1 foot high) Load per square 
, with each bushel. inch in cylinder. 
21 common engines averaged 22,301,735 various, 
Woolf’s at Wheal Vor .e 37,031,002 15°5 lib. 
Ditto Wh. Abraham .. 51,067,670 16°8 
Ditto CILEO. xs -. 20,841,894 4-2 
Ditto Wh. Unity .. 29,417,746 1321 
Dalcouth engine .. Mai 8 AD 9 bs) jo ip 
Wheal Abraham ditto <s. 4 208.022 10°3 
United Mines ditto.. oe, ME. at hd 18:1 
Wheal Chance ditto -- 34,489,691 10°7 
SAFETY LAMP, 
Sir Humphry Davy has made a further discovery in regard to 
combustion, which will prove a very great improvement to his 
safety lamp. He thus describes it in a letter to the Rev. J. Hodg- 
son of Heworth:— 
“| have succeeded in producing a light perfectly safe and 
ceconomical, which is most brilliant in atmospheres in which the 
P4 flame 
