The question of the application of the oxygen is one which must be determined in its manifold bearings mainly by the experiments of chemists and scientific men engaged in industrial work.  Having ascertained the method by which and the limit of cost within which it is possible to use oxygen in their work, it can be seen whether by Brin’s process the gas can be obtained within that limit.

Mr. S.R.  Ogden, the manager of the corporation gasworks at Blackburn, has already made interesting experiments on the application of oxygen in the manufacture of illuminating gas.  In order to purify coal gas from compounds of sulphur, it is passed through purifiers charged with layers of oxide of iron.  When the oxide of iron has absorbed as much sulphur as it can combine with, it is described as “foul.”  It is then discharged and spread out in the open air, when, under the influence of the atmospheric oxygen, it is rapidly decomposed, the sulphur is separated out in the free state, and oxide of iron is reformed ready for use again in the purifiers.  This process is called revivification, and it is repeated until the accumulation of sulphur in the oxide is so great (45 to 55 per cent.) that it can be profitably sold to the vitriol maker.  Hawkins discovered that by introducing about 3 per cent. of air into the gas before passing it through the purifiers, the oxygen of the air introduced set free the sulphur from the iron as fast as it was absorbed.  Thus the process of revivification could be carried on in the purifiers themselves simultaneously with the absorption of the sulphur impurities in the gas.

A great saving of labor was thus effected, and also an economy in the use of the iron oxide, which in this way could be left in the purifiers until charged with 75 per cent. of sulphur.  Unfortunately it was found that this introduction of air for the sake of its oxygen meant also the introduction of much useless nitrogen, which materially reduced the illuminating power of the gas.  To restore this illuminating power the gas had to be recarbureted, and this again meant cost in labor and material.  Now, Mr. Ogden has found by a series of conclusive experiments made during a period of seventy-eight days upon a quantity of about 4,000,000 cub. ft. of gas, that by introducing 1 per cent. of oxygen into the gas instead of 3 per cent. of air, not only is the revivification in situ effected more satisfactorily than with air, but at the same time the illuminating power of the gas, so far from being decreased, is actually increased by one candle unit.

[Illustration:  THE PRODUCTION OF OXYGEN BY BRIN’S PROCESS.]

So satisfied is he with his results that he has recommended the corporation to erect a plant for the production of oxygen at the Blackburn gas works, by which he estimates that the saving to the town on the year’s make of gas will be something like L2,500.  The practical observations of Mr. Ogden are being followed up by a series of exhaustive experiments by Mr. Valon, A.M.  Inst.  C.E., also a gas engineer.  The make of an entire works at Westgate is being treated by him with oxygen.  Mr. Valon has not yet published his report, as the experiments are not quite complete; but we understand that his results are even more satisfactory than those obtained at Blackburn.