Joly 1, 1865.] THE TECHNOLOGIST. 



ON DYEING. 543 



more and more perfect, yet many arts attained, when chemical science 

 was in its infancy, great excellence — an excellence which, in some arts 

 cannot be surpassed in the present day by the most experienced manu- 

 facturers — and in some cases processes have been entirely lost and can- 

 not be recovered by our most skilful chemists. That many chemical 

 phenomena should have been discovered in ancient times, and after- 

 wards lost, is not to be wondered at, for in the early periods of chemical 

 science, many of these phenomena were the result of chance experi- 

 ments, the chemical laws governing the various changes being unknown, 

 and consequently were lost as time lapsed. 



To every seat of the arts chemistry descends, where it changes the 

 forms and the qualities of .the productions of nature, enabling them to 

 be appropriated in a thousand different ways to our wants. The dyer, 

 tanner, distiller, bleacher, the soap and candle-maker, the manufacturer 

 of glass, porcelain, and sugar, the brewer, gas-factor, photographer, the 

 etcher upon copper and steel, the lithographer, and many others, are all 

 more or less beholden to this science for the perfection to which their 

 several arts have arisen. By its aid we learn how to extract the metals 

 from the combinations with which they are found in nature — how to 

 fuse, purify and alloy them. It gives to waste materials new and in- 

 creased value, for the chemist, by research and experiment, points out 

 the application of matters supposed to be effete and useless, to some 

 beneficial purpose. In the present clay the manufacturer must possess 

 a certain amount of chemical and scientific knowledge, so vastly are the 

 arts indebted to chemistry for all improvements in their various pro- 

 cesses, and especially if he would compete successfully with others in 

 his productions. The manufacturer, by pointing out new processes, and 

 discovering new materials, which cheapen the products of his art, is 

 enabled to bring within the reach of the many the comforts and luxuries 

 which otherwise would have been confined to the few. How necessary 

 it is for the manufacturer of soap, if he would successfully and eco- 

 nomically carry on his manipulations, that he should understand the 

 affinities existing between the various oils and alkalies ; to the candle- 

 maker, that he should understand the decomposition of fats and oils 

 into their acids and bases — he must learn the nature of fatty bodies, and 

 know how to separate the superfluous matters of fats and oils from those 

 parts which he requires in his art. The extraordinary improvements 

 that chemistry has effected in this one manufacture is surprising. 

 Before 1811, the candle manufacturer had only tallow, wax, and/perma- 

 ceti at his disposal, and the great desideratum was to obtain substances 

 possessing a certain amount of hardness and compatibility ; the great 

 objection to tallow, besides its disagreeable odour, is its want of uni- 

 formity in consistence — tallow being formed of two fatty bodies, one 

 oily and soft, the other firm and hard ; consequently, when burning the 

 soft portion melts first, and we have what is known as guttering. In 

 1811, a French chemist, M. Chevreul, by his researches, explained the 

 vol. v. 3 M 



