(293.) A farther cause of the uncertainty of the results of such an experiment arises from the possibility that azote may really contribute to the fusion of the mixed mass in the furnace, though its mode of operating is at present unknown. An examination of the nature of the gases issuing from the chimneys of iron-foundries, might perhaps assist in clearing up this point; and, in fact, if such inquiries were also instituted upon the various products of all furnaces, we might expect the elucidation of many points in the economy of the metallurgic art.
(294.) It is very possible also, that the action of oxygen in a liquid state might be exceedingly corrosive, and that the containing vessels must be lined with platinum or some other substance of very difficult oxydation; and most probably new and unexpected compounds would be formed at such pressures. In some experiments made by Count Rumford in 1797, on the force of fired gunpowder, he noticed a solid compound, which always appeared in the gun-barrel when the ignited powder had no means of escaping; and, in those cases, the gas which escaped on removing the restraining pressure was usually inconsiderable.
(295.) If the liquefied gases are used, the form of the iron furnace must probably be changed, and perhaps it may be necessary to direct the flame from the ignited fuel upon the ore to be fused, instead of mixing that ore with the fuel itself: by a proper regulation of the blast, an oxygenating or a deoxygenating flame might be procured; and from the intensity of the flame, combined with its chemical agency, we might expect the most refractory
