On joining my partner after this interview with Miss Mushet, I explained to him what had occurred; he listened to me with surprise, and with more impatience than I had ever seen him evince. He thought that what I had done was most unfortunate and imprudent, since from Miss Mushet's words it was evident that the idea was abroad that I had in some way taken advantage of her father. He feared lest my cheque should be considered evidence of my indebtedness. I was much distressed to find my friend Longsdon so much annoyed, for a more conscientious and just man I never knew; he was, however, somewhat reassured when I told him that I considered it a purely personal matter, and had, of course, drawn the cheque on my private bankers. He said he was glad it could never appear as an act of the firm, though he thought it would be long before I should hear the last of it.

Events proved that he was right, for not many months elapsed (about 1867) before a friend -- I believe a relation of Mr. Mushet -- wrote asking me to make Mushet a small allowance. I objected to do this at first, but afterwards yielded, though I did not then care to give my reasons for doing so. There was a strong desire on my part to make him my debtor rather than the reverse, and the payment had other advantages: the press at that time was violently attacking my patent, and there was the chance that if any of my licensees were thus induced to resist my claims all the rest might follow the example, and these large monthly payments might cease for such a period as the contest in the law courts might last. The annoyance, if nothing else, would have been very great, and I had neither time nor patience to wage a paper war from year's end to year's end with unscrupulous writers. In the hope that an allowance to Mr. Mushet might have the effect of restraining these attacks on me, I offered to pay him £300 a year, aiming at abating an intolerable nuisance which I had no other means of preventing. While we were paying over &process as soon as steel of the proper quality was arrived at, for the continuation of the blowing process until malleable iron was obtained, had the disadvantage of consuming from 2 to 3 per cent. more iron than when steel was made; and, what was still worse, the metal got very much overcharged with oxygen, causing violent ebullition in the mould. I had an idea that this occluded oxygen could be got rid of without any addition to the metal. I had noticed that when super-oxydised molten malleable iron came in contact with the cold-iron mould, it boiled and threw off large quantities of gas, as its temperature was reduced, the action being similar to that which takes place in the cooling of large masses of molten silver, which sputter and make a sort of little volcanic mound on the top of the ingot, owing to the spontaneous disengagement of occluded oxygen. In the case of steel, this throwing off of carbonic acid, or carbonic oxide, gas was a source of great unsoundness in ingots, and appeared to be a very important subject for investigation. I consequently had a small apparatus constructed, with a view of seeing how far this gaseous matter could be prevented from escaping in the form of bubbles by being surrounded with a dense atmosphere, to suppress ebullition; and also how far it could be removed by considerably lowering the pressure of the surrounding atmosphere, thus favouring ebullition and the removal of the gas from the metal.

I may here mention, incidentally, that these experiments were the starting-point of my patents for casting under gaseous pressure, and also under the pressure of an hydraulic plunger, acting direct on the fluid metal. Under this latter patent, I granted a license to Sir Joseph Whitworth to make his compressed steel. The experimental apparatus for removing gas in vacuo just referred to, was simply a short cylindrical vessel, on to which a conical cover was fitted; the flanges which formed the junction between the two were accurately surfaced, and formed an air-tight joint. At the top of the apparatus a small circular piece of plate glass was inserted, through which the eye could, by means of the light emitted by the incandescent metal, see distinctly whatever was going on inside the chamber.

Experimental apparatus for exposing molten steel to the action of a vacuum

This apparatus is shown in section in Fig. 76, page 270. Having converted some pig iron into highly- carburised steel by means of a fireclay blow pipe, a crucible about half filled with this steel was put into the chamber. The pipe and stop-cock shown on one side of it were made to communicate with an exhaust pump, or with an exhausted vessel, the effect of which was at first to cause a few bubbles to rise to the surface of the metal; but only a comparatively gentle ebullition was produced, however high a vacuum was attained. If mild steel, however, was so treated a much more violent ebullition took place; and if a 20-lb. crucible containing about 10 lb. only of wholly decarburised pig iron was put into the chamber,

  By PanEris using Melati.

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