Mushet's claim to have afforded Bessemer the means of making his own process useful is still subject to debate. Unfortunately, documentation of the case is almost wholly one sided, since his biggest publicizer was Mushet himself. An occasional editorial in the technical press and a few replies to Mushet's "lucubrations" are all the material which exists, apart from Bessemer's own story. Mushet and at least five other men patented the use of manganese in steel making in 1856; his own provisional specification was filed within a month of the publication of Bessemer's British Association address in August 1856. So it is strange that Robert Mushet did not until more than a year later join in the controversy which followed that address.[58] In one of his early letters he claims to have made of "his" steel a bridge rail of 750 pounds weight; although his brother insists that he saw the same rail in the Ebbw Vale offices in London in the spring of 1857, when it was presented as a specimen of Uchatius steel![59] Robert Mushet's indignant "advertisement" of January 5, 1858,[60] reiterating his parentage of this sample, also claimed a double-headed steel rail "made by me under another of my patent processes," and sent to Derby to be laid down there to be "subjected to intense vertricular triturations." Mushet's description of the preparation of this ingot[61] shows that it was derived from "Bessemer scrap" made by Ebbw Vale in the first unsuccessful attempts of that firm to simulate the Bessemer process. This scrap Mushet had remelted in pots with spiegel in the proportions of 44 pounds of scrap to 3 of melted spiegel. It was his claim that the rail was rolled direct from the ingot, something Bessemer himself could not do at that time. [58] October 17, 1857, writing as "Sideros" (_Mining Journal_, 1857, vol. 27, p. 723). [59] _Mining Journal_, 1857, vol. 27, p. 871, and 1858, vol. 28, p. 12. [60] _Ibid._ (1858), p. 34. [61] Mushet, _op. cit._ (footnote 46), p. 12. The phrase quoted is typical of Mushet's style. This was the beginning of a series of claims by Mushet as to his essential contributions to Bessemer's invention. The silence of the latter during this period is impressive, for according to Bessemer's own account[62] his British Association address was premature, and although the sale of licenses actually provided him with working funds, the impatience of those experimenting with the process and the flood of competing "inventions" all embarrassed him at the most critical stage of this development of the process: "It was, however, no use for me to argue the matter in the press. All that I could say would be mere talk and I felt that action was necessary, and not words."[63] [62] Bessemer, _op. cit._ (footnote 7), pp. 161 ff. and 256 ff. [63] _Ibid._, p. 171.