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TRANSACTIONS OF THE SECTIONS. 43 
On the Slacking of Quicklime. By Joun Davy, M.D., F.R.S., Se. 
The object of the author in this communication was twofold :—first, the giving 
an account of certain experiments, the results of which seemed to show that lime 
is capable of forming with water a subhydrate, attended with the evolution of little 
heat; next, the suggesting the use of lime in collieries as a substitute for gunpow- 
der in blasting, founded on the fact of the high temperature, attended with the 
production of steam, occasioned by the quenching quicklime,—that is, its conver- 
sion into a hydrate,—yet not sufficiently high to inflame any inflammable gas. He 
concluded with expressing the hope that a trial of the suggestion would be made 
in a colliery, being so easy of execution and attended with no danger—the great 
objection to the use of gunpowder. His own trials, he stated, made with borings 
into hard sandstone, had not succeeded, which is not surprising considering the re- 
sistance offered—so much greater than from coal—and the small quantity of lime 
employed. 
On a new Gas-Furnace for melting Gold, Silver, Copper, Cast Iron, Glass, 
§e., by means of Coal-gas, without the aid of a bellows or tall chimney. 
By G. Gorn. 
This furnace consists of a stout cylinder of fire-clay, about 10 inches high and 
6 or 8 inches wide, enclosed in a sheet-iron casing, to the lower and back part of 
which is affixed a short chimney: the casing is supported by three iron legs about 
-15 or 18 inches high. Inside the clay cylinder is placed a shorter and thinner 
clay cylinder or cupola, having three clay pegs projecting from its inner side near 
the top, for supporting the crucible. Both the cylinders are open at their ends, 
and rest upon the bottom of the iron casing. The outer clay cylinder is covered at 
the top by a thick circular plate of fire-clay, with a hole in its centre for inserting 
or removing the crucible, &c. ; and this hole is closed by a plug of fire-clay. The 
iron casing has a large hole in the middle of its bottom part under the cupola, be- 
neath which is fixed a peculiar corrugated gas-burner ; so that the flame passes wu 
inside the cupola, surrounding the crucible, then out at the top of the cupola, an 
down the outside between it and the outer cylinder, to a hole entering the 
chimney. 
The Mediiesi-siccd furnace will melt half a pound of copper, or six ounces of 
cast iron. One ounce of copper has been melted in it in 2} minutes, one ounce of 
cast iron in 3 minutes, five ounces of copper in 4} minutes, and three ounces of 
cast iron in 5 minutes. The second-sized furnace will melt fifty ounces of copper, 
or forty ounces of cast iron; it has melted sixteen ounces of copper in 8 minutes. 
The furnace is portable, requiring no brickwork erections or fixed chimney; it 
may be placed anywhere, and used in any situation where gas is available; it is 
safe in action, free from dust, and produces no smoke. A further great advantage 
is “the perfect accessibility which it permits to the melted metal, and the protec- 
tion of the fused metal from oxidation by means of the layer of flame which during 
the action of the furnace plays over the mouth of the open crucible and excludes 
the atmospheric air. Thus the advantages of a covered crucible are gained, whilst 
the contents of the crucible are perfectly accessible to examination or manipula- 
tion.” This also enables oxidable metals and alloys to be melted in an open 
crucible without the addition of a flux or reducing agent. 
The furnaces are suitable for jewellers, dentists, analytical chemists, and all 
persons requiring small crucibles quickly heated to high temperatures. They may 
be obtained of EK. W. Ball, 11 Broad Street, Islington, Birmingham. 
On the Commercial Advantages of a new Carbonate of Soda, 
By M. L. Kusstzr. 
He refers to the ‘Comptes Rendus’ of the French Academy for January 12, 1863, 
for his description of the facility of obtaining, with simple Breanne, beautiful 
erystals of this salt containing one equivalent of water. From their different 
crystalline form they cannot be confounded with ordinary crystals of soda. They 
are right prisms with square bases, sometimes terminated by a right face, but 
oftener by a prismatic or pyramidal summit, 
