Norwich, Yorkshire, Gloucestershire, and various other parts of the British dominions. The author has, in treating of the various matters to be dyed, adopted nearly the same arrangement as that which appears in the _Title_, taking _Cotton_ first, in consequence of its having the least affinity for dyeing bodies. He has taken _Silk_ next, which has a greater affinity for many dyes, and, when dyed, yields colours more permanent than cotton. _Wool_ he has not placed entirely last, although many of the colours which it receives from the dyer are complex. The _black dyeing_ of _cotton_ and _silk_ is placed after the processes of black for wool, as likewise the _Turkey red_, _&c._ these being naturally difficult to perform. _White_ and _black_ have been considered colours by dyers, and with propriety, black forming a part of slate, grey, &c. White is seldom pure; in proportion to its clearness and purity will the colours be with which it is dyed. In regard to _black dye_, and particularly _cotton black dye_, the author does not know any simple and concise theory, consistent with chemical principles. He flatters himself, however, that from his extensive experience, his observations are founded on interesting facts. Cotton, for instance, will take fast blues from the cold indigo vat; this vat, with the combination of iron, and in a heat no greater than the hand can bear, will easily produce all shades of grey, slate, &c. Many of these colours may be done by logwood instead of the blue vat, and in the same heat of the dye bath; so cotton likewise, whether in pieces or skeins, may be dyed brown, fawn, drab, &c. in consequence of the great affinity which cotton has for acetate and sulphate of iron. With respect to _black_, it should be also observed, that few substances are known which yield _by themselves_ a good black. The juice of the _cashew nut_ communicates, however, a black colour, which resists not only washing, but even boiling with soap and alkaline leys. It is used for marking linen. The _Toxicodendron_ yields a juice which produces nearly the same effect. Some other vegetables also produce black dyes, but all of them in such small quantities as not to be available for the purposes of art; nor do they, besides, produce blacks equal to those formed in the dye-house. _Blue_, _red_, and _yellow_ are admitted to be three distinct colours. In many of the _browns_, red and yellow are combined naturally in the drugs from which they are produced, and so they are in logwood. Blue, red, and yellow, are developed by _iron_, whether in the state of an acetate or sulphate. It may be useful, before we proceed any farther in noticing the theories of dyeing, to give a brief description of the _Drugs Applicable to Dyeing._