Drunkenness or great exhaustion may also explain certain cases.

In substantiation of the possibility of Taylor's instances several prominent physiologists have remarked that persons have endured severe burns during sleep and have never wakened.
There is an account of a man who lay down on the top of a lime kiln, which was fired during his sleep, and one leg was burned entirely off without awaking the man, a fact explained by the very slow and gradual increase of temperature.
The theories advanced by the advocates of spontaneous human combustion are very ingenious and deserve mention here.

An old authority has said: "Our blood is of such a nature, as also our lymph and bile: all of which, when dried by art, flame like spirit of wine at the approach of the least fire and burn away to ashes." Lord Bacon mentions spontaneous combustion, and Marcellus Donatus says that in the time of Godefroy of Bouillon there were people of a certain locality who supposed themselves to have been burning of an invisible fire in their entrails, and he adds that some cut off a hand or a foot when the burning began, that it should go no further.

What may have been the malady with which these people suffered must be a matter of conjecture.
Overton, in a paper on this subject, remarks that in the "Memoirs of the Royal Society of Paris," 1751, there is related an account of a butcher who, opening a diseased beef, was burned by a flame which issued from the maw of the animal; there was first an explosion which rose to a height of five feet and continued to blaze several minutes with a highly offensive odor.

Morton saw a flame emanate from beneath the skin of a hog at the instant of making an incision through it.
Ruysch, the famous Dutch physician, remarks that he introduced a hollow bougie into a woman's stomach he had just opened, and he observed a vapor issuing from the mouth of the tube, and this lit on contact with the atmosphere.