On the Economy of Machinery and Manufactures

by Charles Babbage

290. The circumstance of so large a portion of the air(3*) driven into furnaces being not merely useless, but acting really as a cooling, instead of a heating, cause, added to so great a waste of mechanical power in condensing it, amounting, in fact, to four-fifths of the whole, clearly shews the defects of the present method, and the want of some better mode of exciting combustion on a large scale. The following suggestions are thrown out as likely to lead to valuable results, even though they should prove ineffectual for their professed object.

291. The great difficulty appears to be to separate the oxygen, which aids combustion, from the azote which impedes it. If either of those gases becomes liquid at a lower pressure than the other, and if those pressures are within the limits of our present powers of compression, the object might be accomplished.

Let us assume, for example, that oxygen becomes liquid under a pressure of 200 atmospheres, whilst azote requires a pressure of 250. Then if atmospheric air be condensed to the two hundredth part of its bulk, the oxygen will be found in a liquid state at the bottom of the vessel in which the condensation is effected, and the upper part of the vessel will contain only azote in the state of gas. The oxygen, now liquefied, may be drawn off for the supply of the furnace; but as it ought when used, to have a very moderate degree of condensation, its expansive force may be previously employed in working a small engine. The compressed azote also in the upper part of the vessel, though useless for combustion, may be employed as a source of power, and, by its expansion, work another engine. By these means the mechanical force exerted in the original compression would all be restored, except that small part retained for forcing the pure oxygen into the furnace, and the much larger part lost in the friction of the apparatus.

292. The principal difficulty to be apprehended in these operations is that of packing a working piston so as to bear the pressure of 200 or 300 atmospheres: but this does not seem insurmountable. It is possible also that the chemical combination of the two gases which constitute common air may be effected by such pressures: if this should be the case, it might offer a new mode of manufacturing nitrous or nitric acids. The result of such experiments might take another direction: if the condensation were performed over liquids, it is possible that they might enter into new chemical combinations. Thus, if air were highly condensed in a vessel containing water, the latter might unite with an additional dose of oxygen, (4*) which might afterwards be easily disengaged for the use of the furnace.

293. A further 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 enquiries 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 gunbarrel 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 ore to be smelted, and that ultimately the metals at present almost infusible, such as platinum, titanium, and others, might be brought into common use, and thus effect a revolution in the arts.

296. Supposing, on the occurrence of a glut, that new and cheaper modes of producing are not discovered, and that the production continues to exceed the demand, then it is apparent that too much capital is employed in the trade; and after a time, the diminished rate of profit will drive some of the manufacturers to other occupations. What particular individuals will leave it must depend on a variety of circumstances. Superior industry and attention will enable some factories to make a profit rather beyond the rest; superior capital in others will enable them, without these advantages, to support competition longer, even at a loss, with the hope of driving the smaller capitalists out of the market, and then reimbursing themselves by an advanced price. It is, however, better for all parties, that this contest should not last long; and it is important, that no artificial restraint should interfere to prevent it. An instance of such restriction, and of its injurious effect, occurs at the port of Newcastle, where a particular Act of Parliament requires that every ship shall be loaded in its turn. The Committee of the House of Commons, in their Report on the Coal Trade, state that,

'Under the regulations contained in this Act, if more ships enter into the trade than can be profitablv employed in it, the loss produced by detention in port, and waiting for a cargo. which must consequently take place, instead of falling, as it naturally would, upon particular ships, and forcing them from the trade, is now divided evenly amongst them; and the loss thus created is shared by the whole number.' Report, p. 6.

297. It is not pretended, in this short view, to trace out all the effects or remedies of over-manufacturing; the subject is difficult, and, unlike some of the questions already treated, requires a combined view of the relative influence of many concurring causes.