Volume 1

A description of a new horse shoe which expands to the foot / [Bracy Clark].

  • Bracy Clark
Date:
1827
Catalogue details

Licence: Public Domain Mark

Credit: A description of a new horse shoe which expands to the foot / [Bracy Clark]. Source: Wellcome Collection.

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    pe) certained exactly what the metal will bear; after this there is pretty good security in their wear- ing well, and a whole batch of shoes may be tried, or a single shoe. We may also judge prettly well of this metal by breaking a shoe ; if the conversion of the metal has been perfect, the metal generally looks bright and sparkling like wrought metal, at least in degree; but if the quality of cast metal prevails, a black hue or grain is seen with hardly any metallic splendor. The manner of effecting this change in cast metal has not been commonly divulged, but has been practised with considerable secrecy by those who manufacture it. I have been curious to learn what I could respecting this process, and: what I have been able to obtain I shall keep:no secret. I first sought the patent office in order to observe what the original patentee had disclosed, and found he had, been pretty free and communicative. His patent is dated June 26th, 1804, and after the usual preamble states, that he uses for this purpose what he calls The Steel converting Furnace ; and that the cast metal placed in this furnace is to be exposed to the action of iron stone or iron ore, or some metallic oxyd, lime, or any combination of these, reduced to small pieces, or to pow- der, that they might combine with, or consume, the carbon of the cast iron. That the heat should be applied for a long period, and so intensely as to combine the carbon with the above substances, or effect the decomposition of the carbon. If the iron is to be rendered perfectly malleable, from one-half to two-thirds of it’s weight of sron-stone is to be employed; if only partially so, a less quantity will suffice. Five or six days will, in general, be found sufficient to continue the heat, which towards the close of the process cannot be too great short of fusing the iron. The cast iron should not be too thick, as it will much lengthen the process. The length of time for the conversion, will also much depend on the nature of the iron used. The iron to be converted should be placed in alternate layers with the composition ; and to prevent the iron ore from adhering to the cast metal, a thin layer of sand should be interposed. — . Such is the patentee’s setting forth of his process, in which there appears much candour, and of unreserved open communication. The horse ‘shoe being very solid, compared with the articles they were generally used to con- yert, it will no’/doubt require a much longer time of exposure to the fire. The conversion is, how- ever, as perfectly practicable with thick as well as with thin metal; since we have received formerly from Wolverhampton some tablet shoes for cart horses, which wore remarkably well and appeared to be converted quite through their substance. LT have also learnt: from conversations with the manufacturers, that it is not all cast iron that will admit of conversion; but that the iron which is found in Cumberland, and is obtained from Lancashire under the name of Ulverstone. pig, is by far the best. The Shropshire iron runs when melted, and I think he observed, very fluid and thin, and to convert it required an intense degree of heat; but what is called Old Park pig will do better than any other. I have also been told that most of the Swedish pig iron is particularly well suited for this purpose. A Mr. Shuter of Wolverhampton, a manufacturer of this article, was explicit enough on this art to inform me that iron pots were used in the conversion, standing one over another in tiers; these were closely cemented up with wet sand, so‘as to be hermetically closed; for the least aperture would cause the flame’ to rsh’in, and burn away or scale the metal. The dimensions of ore of these ovens was about a cube of seven or eight feet, with intervals between the rows of pots for the passage of the fire. These pots were of a cylindrical form, with lids to them of about a hundred
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