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perature at which the products of combustion left the chamber. 
It is not difficult to conceive that by this arrangement, and with 
its power of accumulation, any degree of temperature may be 
obtained in the furnace chamber, without having recourse to 
purified gas, or to an intensified draught. Where the tempe- 
rature of the melting chamber has certainly exceeded 4,000 
degrees of Fahrenheit, the products of combustion escape into 
the chimney at a temperature of only 240 degrees. The prac- 
tical result of this regenerative system is stated to be, that a ton 
of steel requires by the ordinary method about three tons of 
Durham coke, — which, being estimated as coal, will be about 
four tons, — to melt it, whereas in Siemens’s furnace, the melting 
is effected with twelve hundred-weight of ordinary coal. This 
economy is produced by reserving the heat, by means of the re- 
generator, which is ordinarily allowed to escape by the chimney. 
Another plan for consuming coal with economy has been re- 
cently introduced by Mr. T. E. Crampton, and is now in use at 
the Eoyal Arsenal, Woolwich, and at the Bowling Iron Works, 
in Yorkshire. Instead of converting the coal into gas, as in the 
Siemens’ process, the coal is reduced by Mr. Crampton to a 
very fine powder, and then blown into the heated chamber by 
means of a fan-blast. By this arrangement the perfect com- 
bustion of the coal is produced, and a heat of the highest in- 
tensity can be obtained. The utilisation of this heat, without 
waste, when it is produced, is an important question still re- 
quiring careful attention. There are several other experiments 
being carried out with a view to the economical use of coal, 
but the two to which we have alluded give up to the present 
time the best results. Still, with these we allow more than one 
half of the heat latent in the coal to escape us. The subtle 
element eludes our grasp — our charms are powerless to chain 
the sprite ; he will not be bound to labour for us, but passes off 
into space, regardless of the human Prospero whose wand of 
science he derides. 
In conclusion, our philosophy has enabled us to determine 
the heat-value of our coal-fields, and to prove that all this heat 
has a solar origin. Our science has shown us that although we 
can eliminate all this heat, we cannot use it. There is an im- 
mense quantity constantly passing into space as radiant heat 
which we cannot retain. 
The circle of action between the vegetable and the animal 
world, is a beautiful and a remarkable provision. The animal 
burns carbon and sends into the air carbonic acid (a compound 
of carbon and oxygen), the vegetable breathes that carbonic 
acid and decomposes it, the carbon is retained and the oxygen 
liberated in purity, to maintain the life and fire-supporting 
principle of the atmosphere. Changes similar to these may be 
