INFLAMMATION, in chemistry, is combus tion attended with flame : under the arti cle COMBUSTION, we have referred to the spontaneous inflammation of certain bo dies, in peculiar circumstances, and like wise to the combustion of living individu als in the human species. We shall in this place mention some of the causes of spon taneous inflammation. The heat produced by friction ; the slacking of lime when in contact with combustible matter ; the fer mentation of hay, dunghills, &c. are well known. Many vegetable substances, high ly dried and heaped together, will heat, scorch, and at last burst in a flame. A mix ture of linseed, or rape oil, with almost any dry vegetable fibre, as hemp, cotton, matting, &c. and still more if united to certain carbonaceous matters, will in time, if in a warm place, burst out into a flame. To this circumstance many alarming and destructive fires are to be imputed, which at the time were supposed to have been occasioned by wilful crime. In 1781 a large magazine of hemp was destroyed, in this way, at Constradt : and in the summer of 1794 an accident of this sort happened at Gainsborough, with a bale of yarn ac cidentally'soaked in rape oil, which, after remaining in the warehouse for several days, began to smoke, and finally to burst out into a most violent flame. A similar accident happened at Bombay. A bottle of linseed oil had been thrown down in the night, the oil had penetrated into a chest of coarse cotton cloth, and in the morning the cloth was found reduced nearly to a cinder, and the wood of the chest completely charred in the inside.
An experiment was immediately made to ascertain the true cause : a piece of the same cloth was dipped in the same sort of oil, and shut up in a box, and in three hours it was found hot, and on opening the box it burst into a flame. Hence the spontaneous combustion of wool, or woollen yarn, which has some times happened when large quantities have been kept in heaps without the ac cess of fresh air. The oil with which it is dressed seems to be the chief cause of combustion. Wheaten flour and charcoal reduced to powder, and heated in large quantities, have been known to take fire spontaneously.
The cases of the spontaneous human combustion have never been satisfactori ly accounted for ; the facts themselves seem to be well authenticated; two are recorded in the Philosophical Transac tions, and referred to under COMBUSTION. They ought, however, to hold out a lesson of warning to those habitually given to excess with regard to spirituous liquors ; for, in every case, the subjects of this ter rible calamity were drunkards, whose favourite liquor was alcohol, in the shape of brandy, gin, &c.