(b) An inflammatory red bounding line round the circumference.
(c) Inflammatory redness of the base, and the papillæ of the skin.
(d) The presence of pus, which would indicate that the person had lived at least thirty-six hours after the burn had taken place.
In burns produced after death, the surface and substance of the skin is of a dull white colour, dotted with grey openings of the sudoriferous and sebaceous ducts, and the subcutaneous tissues are uninjected. Vesicles produced by burns may have to be distinguished from the phlyctænæ, the result of advanced putrefaction. The latter possesses none of the characteristics of the former.
If a vesicle present the following characteristics it may be accepted as a post-mortem origin without doubt: if it be small and its contents scanty, if the fluid it contain be free from albumin and chlorides, if it contain air, and if there be no signs of inflammatory reaction.
Was the burning homicidal, suicidal, or accidental?—No general rules for guidance can be here laid down. In most cases the conditions under which the body is found will point less to suicide than to homicide or accident. In cases of murder, the body is often burnt in the attempt to destroy all traces of the crime. It must, however, be borne in mind that intense heat applied to the body may give rise to a wound on the surface like that caused by a cutting instrument. Casper mentions such a case, in which a wound was found over the liver, due to the application of intense heat to the body. The conjunction of robbery will greatly assist in helping to solve the difficulty. It may be very confidently stated that to dispose of a body by burning is no easy matter.
Preternatural Combustibility
The possibility of “spontaneous combustion” occurring in bodies during life has been mentioned in the earlier writings on medical jurisprudence, and cases have been recorded in which it has been alleged to have taken place. Up to the present time no undoubted case of “spontaneous combustion” during life has been seen. On the other hand, the possibility of its occurrence is contra-indicated by the following facts: that the human body must consist of 75 per cent. of its weight of water, to be compatible with life, and that a dead body steeped in methylated spirit for many months or even years will never be consumed, if set on fire, in the rapid and complete manner alleged as occurring in cases of so-called “spontaneous combustion.”
A case is recorded by Beatson (B. M. J., vol. i., 1886, p. 295) of a man, subject to foul eructations from the stomach, who got out of bed during the night and struck a match to see the time; while blowing out the light his breath took fire, producing an explosive noise sufficiently loud to awaken his wife. Such cases are very rare.
It is a fact that by the action of certain micro-organisms upon organic matter inflammable gases are produced. That such an occurrence is possible, in the dead human body, is supported by cases recorded by Gull (Med. Times and Gazette, 1885) and Reynolds (Med. Chron., 1891). In Gull‘s case inflammable gases escaped through punctures made into the abdomen, and they burned spontaneously on contact with the air. In Reynold‘s case no flames were seen, but extensive and deep marks of burning were present, especially on the trunk and thighs. It has been suggested that the habitual use of alcohol in excess during life renders the tissues of the body more inflammable, but the matter is not yet decided. Tissues steeped in alcohol are not rendered more inflammable.