672 
POPULAR SCIENCE REVIEW. 
bourliood of Calama. But the cost of transporting the ore by pack mules to 
the coast is so great from there being no vegetation and no water for a dis- 
tance of ninety miles, that until a road for wheeled vehicles be made, the 
immense mineral wealth of that locality will lie dormant. The same causes 
militate against the exportation of borax, fields of which, miles in extent, 
exist near Ascotan, at the foot of the Andes, about one himdred miles east 
of Calama. The projected railway from Iquique, in Peru, to the interior of 
the Eepublic, for which ^Messrs. Peto & Betts entered into a contract with the 
Bolivian Government, has been for the time abandoned, in consequence of 
the late revolution which overthrew the constitutionally-elected President. 
Formation of Steel by the introduction of Gases. — At a late meeting of the 
, French Academy of Science, M. Berard brought before the notice of the 
savants his new method of preparing steel by introducing certain gases into 
heated metal. Tliis process consists essentially in alternately oxidizing and 
reducing cast iron in a furnace suited to the purpose. The oxidation is pro- 
duced in one portion of the cast iron by the introduction of atmospheric air, 
and the reduction in another by a mixture of hydrogen and carbonic oxide. 
After twelve or fourteen minutes, the processes are reversed, the portions 
previously submitted to oxidation being reduced, and vice versa. Any oxygen 
evolved is absorbed by burning coke placed in a proper position. When 
this alternate action is found by trial to have been conducted long enough, 
the operation is stopped — decarbonation being the terminating process. 
During oxidation the bases of the metals proper and of the earths are oxi- 
dized ; the sulphur, phosphorus, &c., form acids, and then escape. During 
reduction the iron is brought to the metallic state, and the earths separate as 
scoria, any remaining sulphur, phosphorus, &c., being eliminated as acids, 
and some carbon is restored to the iron. A high temperature is produced 
during “ oxidation,” and a low one during “ reduction.” Ten or twelve tons 
are manipulated at each operation in the inventor’s establishment, and the 
steel produced is said to have all the properties of the ordinary kind. 
Co'osumption of Wood-fuel in France. — M. Becquerel’s memoir affords 
some very curious information regarding the quantity of fuel consumed at 
various periods, both for domestic and manufacturing purposes. The writer 
tells us that under the Consular period, from 1801 to 1804, the consumption 
of wood was the most considerable ; it fell materially under the Imperial era, 
rose again under the Eestoration, and declined again from 1826 to 1834. 
The fall continued until 1848 to such an extent as to cause much anxiety to 
landed proprietors ; but from that period a rise began which has ever since 
continued. The consumption of charcoal increases in proportion to the 
population, because the poor find it cheaper than sea-coal. Nevertheless, 
the consumption of the latter has rapidly increased. In 1821, when pit- 
coal was not in common use for domestic purposes, the amount of wood 
consumed was equivalent to 2 '5 quintals of pure carbon. This quantity has 
been constantly diminishing, so that in 1861 it was only represented by an 
equivalent of 0'687 of a quintal of pure carbon, the difference having evi- 
dently been made up by pit-coal. Now, if, says M. Becquerel, the production 
of the latter were by any chance to decline, it would become necessary to 
fetch Avood from a great distance in order to satisfy the wants of the capital, 
and its price would consequently experience a rise ; but, were the clearing 
