On the manufacture of chlorine : a lecture, delivered, at the request of the Council of the Society of Arts, before the Chemical Section of that Society, May 22nd, 1874, A.W. Williamson ... in the chair / by Walter Weldon.

Walter Weldon

Date:: 1874

Credit: On the manufacture of chlorine : a lecture, delivered, at the request of the Council of the Society of Arts, before the Chemical Section of that Society, May 22nd, 1874, A.W. Williamson ... in the chair / by Walter Weldon. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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$liis fatlier-in-law, near Glasgow, in the year 17S7, being the year of Scheele's death. The process soon 2pread into nearly all the bleach-works of Great Britain; bnt it was attended by two serious inconveniences. Owing to chlorine- water being practically incapable of transport, each bleacher had to manufacture his own chlorine; and owing to'its tendency to give off its dissolved gas, its use was all but intolerable to the workmen. JMany attempts were made to remedy these disadvantages, and they finally resulted, in 1798, in the discovery, by ]\Ir. Charles Tennant, of Glasgow, that dry slaked lime would absorb more than half its weight of chlorine gas, giving a product,—since become so well known as bleaching-powder, or chloride of lime,—which could be both stored and transported with the utmost facility, and which would yield, on treatment with water, a bleaching solution, having all the advantages of chlorine-water, ■without cither of its disadvantages. I am not sure that our time will peimitour doing so, but we propose to try to make a little of this product. At the bottom of the glass trough on the table there is some dry slaked lime, and Mv. Bunker will put a cover on the trough, and then send into it a little chlorine: which he will generate, this time, by means of a product similar to that which we hope to produce In two of the jars into which we are blowing air. I will ask him, however, ■first to take out a little of the lime, in order that, if our time permits us to complete the experiment, you may sec the difference between the body which we put into the trough and the product which we hope to take out of it. When Mr. Tennant first manufactured bleaching-powder, he sold it at one-and-sixpence per pound. Its present price is about £10 per ton, or very little over one penny per pound. Of it and Its equivalent In chlorate of potash we now make in Great Britain one hundred thousand tons per annum, so that the annual value of the British chlorine manufacture is just about a million sterling. We manu-$