XVII. Experiments and observations to investigate the nature of a kind of steel, manufactured at Bombay, and there called Wootz: with remarks on the properties and composition of the different states of iron

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Doctor Scott , of Bombay, in a letter to the President, acquaints him that he has sent over specimens of a substance known by the name of wootz; which is considered to be a kind of steel, and is in high esteem among the Indians. Dr. Scott mentions several of its properties, and requests that an inquiry may be instituted to obtain further knowledge of its nature. This gentleman informs the President, that wootz " admits of a harder temper than any thing known in that " part of India; that it is employed for covering that part of " gun-locks which the flint strikes: that it is used for " cutting iron on a lathe; for cutting stones; for chizzels; for making files; for saws; and for every purpose where " excessive hardness is necessary. ” Dr. Scott observes that this substance " cannot bear any thing beyond a very slight red heat, " which makes it work very tediously in the hands of smiths; " and that " it has a still greater inconvenience or defect, that " of not being capable of being welded with iron or steel; " to which therefore it is only joined by screws and other " contrivances." He likewise observes, that when wootz is “ heated above a slight red heat, part of the mass seems to “ run, and the whole is lost, as if it consisted of metals of " different degrees of fusibility. " We learn also from Dr. Scott's letter, that “ the working with wootz is so difficult, that it is a " separate art from that of forging iron." It will be proper also to notice his observation, that “ the magnetical power in "an imperfect degree can be communicated to this substance." § 2. Mechanical and obvious Properties The specimens of wootz were in the shape of a round cake, of about five inches in diameter, and one thick; each of which weighed somewhat more than two pounds. The cake had been cut almost quite through, so as to nearly divide it into two equal parts. It was externally of a dull black colour; the surface was smooth; the cut part was also smooth, and, excepting a few pinny places and small holes, the texture appeared to be uniform. It felt about as heavy as an equal bulk of iron or steel. It was tasteless and inodorous. No indentation could be made by blows with a heavy hammer; nor was it broken by blows which I think would have broken a like piece of our steel. Fire was elicited on collision with flint. Under the file I found wootz much harder than common bar steel not yet hardened, and than Huntsman' s cast steel not yet hardened. It seemed to possess the hardness of some kinds of crude iron, but did not effectually resist the file like highly tempered steel, and many sorts of crude iron: for although the teeth of the file were rapidly worn down and broken, the wootz. was also reduced to the state of filings The filed surface was of a bright bluish colour, shining like hardened steel; but some parts were brighter than others; and the most shining places seemed to be the hardest parts : hence perhaps the reason of the surface being uneven, and a little pinny . Notwithstanding this uneven and pinny appearance of the filed surface, a polish was produced, which was I think at least equal, if not superior, in brilliancy and smoothness to that of any steel I ever saw. The wootz filings were attracted by the magnet like common iron filings.