KYANIZINO. Lignin has also a strona.
at traction for alumine ; and hence linen, cotton, paper, and other forms of this fibre, may be aluminized by steeping them in hydrated alumina, diffused through water ; or, more effectively by soaking them in certain aluminous solutions, dry ing them, and afterwards washing out the excess of the salt. It is in this way that cotton goods are impregnated with alumine for the purpose of dyeing and calico printing. Other metallic oxides exhibit similar attractive powers, espe cially the oxide of iron.
The analogy that exists between the composition of sugar, gum, starch, and even vinegar and lignin, suggests the possibility of the conversion of those proximate elements into each other ; and it has accordingly been found that by carefully roasting pure and fine sawdust, it is rendered partially soluble in water, and that a part of it is converted into a nutritious substance, probably intermedi ate between sugar and starch ; and which when mixed with a little flour, yields a palatable bread, not very unlike that mado by some of the inhabitants of the north ern parts of Europe of the bark of trees.
Mixed with sulphuric acid, lignin passes into gum ; and from this sugar may be obtained by boiling it for some hours in a very dilute sulphuric acid; this sugar, when purified, much resembles grape or honey sugar. By this process rags may be converted into nearly their own weight of this peculiar saccharine matter. The production of vinegar by the de structive distillation of wood was origi nally suggested about the middle of the 17th century, by Glauber, a celebrated German chemist of that time ; it has lately become a very important branch of manufacture in this country. Upon the whole, there are very few pro ducts equally important with lignin in their applications to the useful and orna mental arts.