wounds, if fired at close quarters at an exposed part of the body. A wound so produced presents a lacerated appearance, and is blackened and burned. Some of the undeflagrated particles of gunpowder may be driven into the skin, giving to it a peppered appearance.

CICATRISATION OF WOUNDS

The identity of a person, living or dead, and the correctness of a statement made by an accused person, may sometimes be determined by the examination of a cicatrix. Although the time at which a particular wound was inflicted may become an important medico-legal question, yet there are no appearances in a cicatrix by which this can be determined, beyond the rough idea of its duration that can be gained from an observation of the colour of the scar. The questions, in connection with cicatrices, that may be of medico-legal importance are the following:

I. Does a cicatrix always result from a wound? The answer to this is yes, although slight punctures or the wounds produced by leech-bites, affecting only the surface of the skin, may leave no trace after a few weeks or months.

II. May cicatrices become so changed by time as to be no longer recognisable ?-Permanent cicatrices are left by the healing of wounds that have involved loss of substance of the true skin, by wounds healing by granulation, by the pustules of small-pox, by setons and issues, and probably from vaccination if efficiently performed. Cicatrices increase in size during the process of growth of individuals. The growth of vaccination scars has frequently been noticed. Adams found, in the case of an infant on whom the operation had been efficiently performed, that a cicatrix had doubled in length and greatly increased in width after eighteen years.

III. What colour or colours may a cicatrix possess at different periods? In an early stage a cicatrix is softer and redder than the surrounding skin; the colour then fades to

brown, and later the cicatrix becomes white, hard, smooth and shining.

IV. What are the peculiar characters of cicatrices? They are of smaller size than the original wound, and are usually depressed. Cicatrices are fibrous in structure, and are destitute of hairs, sweat glands, sebaceous glands, fat, and pigment. A scar upon a negro is white.

CHAPTER XXIX

Burns and scalds-Causes of death from burns-Distinction between burns produced before and after death-Wounds upon the burned- Preternatural combustibility of the human body.

A burn is an injury to the body caused by heat brought to bear upon it by contact with heated solid or molten bodies, or by flame or radiant heat. Injuries resulting from corrosive liquids, such as the strong mineral acids and alkalies, are popularly termed burns, and are so designated in the statutes.

A scald is an injury produced by a liquid, heated above a certain point, or by steam applied to the surface of the body, or within the mouth or other cavities.

Neither a burn nor a scald appears to be considered as a wound in law; in the statute on wounding they are included among bodily injuries dangerous to life.

The intensity of a burn is proportionate to the temperature, area, and duration of action of the causal agent; it varies from a slight redness to a complete charring of the tissues. Metals heated to redness or in a molten state produce very severe burns, especially as in the latter state partial adhesion of the solidified mass occurs to the affected part. Burns and scalds are dangerous in proportion to the severity of the injuries they produce, both as regards the extent of surface of the skin involved, and the depth to which they extend; to some extent the localisation of the lesion affects the danger. The extent of the surface of skin involved in a large superficial burn is likely to be more dangerous than a severe burn of a small part of the

body, provided the locality of the latter is not exceptionally dangerous. If a superficial area equal to about one-third of the entire body-surface be destroyed, death is almost certain to ensue. In other words, the prognosis becomes unfavourable in proportion to the extent of surface involved. The explanation. of this is that there is a greater implication of sensory nerves in a burn of large area, and a greater extent of skin is prevented from doing its work of excretion and heat regulation. In connection with prognosis, other circumstances have to be taken into consideration, such as age, constitution, and the character of the burn. Burns are more dangerous in the young and in the cases of weak people; more dangerous on the trunk than on the limbs, and more dangerous if in separate patches than if continuous, provided they are of equal extent.

Extent of burns.-Dupuytren has classified burns according to their degree or extent as follows:

1. Superficial inflammation of the skin, without vesication. 2. Severe inflammation of the skin, accompanied by vesication; the blisters contain serum, which may be clear, opaque, or bloody. If the cuticle be removed, the true skin is found very red, and later on secretes pus.

3. Destruction of the superficial part of the true skin, forming an eschar, which may be hard and brown or black if resulting from a burn with a solid, or soft and yellow if made by a liquid. The surrounding skin is red and blistered. These burns leave cicatrices, which are white and shining.

4. Destruction of the skin as far as the subcutaneous tissue. These burns differ from the last-mentioned in the deeper destruction of the parts, and in the thickness of the sloughs. They leave cicatrices, which are puckered, and depressed below the level of the skin.

5. The destruction involves the entire skin, the subcutaneous cellular tissue and a portion of the muscles. The general character is the same as in the last-mentioned.

6. Complete charring of the burnt part, as when a portion

of the body is burnt by fire.

Causes of death from burning.-Death from burning may result from a variety of causes, and may be direct or indirect. The following are the various ways in which death may be caused by burning :

I. Suffocation. This may result from want of air, or by poisoning from the inhalation of carbon dioxide or carbon monoxide (carbonic oxide). If death occur from carbon dioxide poisoning, the blood is of a dark colour; if from carbonic oxide, it is of a bright red colour.

II. Shock.

III. Stupor. This especially occurs in connection with. severe burns or scalds inflicted on children. The coma very closely resembles that of opium or other narcotic poisoning.

IV. Enteritis and ulceration of the bowels.-The ulceration is especially apt to occur in the duodenum; it is probably due to thrombosis of a vessel supplying a portion of the mucous membrane, and consequent necrosis of the part from the cutting off of the blood supply.

V. Bronchitis. From irritation of the bronchial mucous membrane, set up by the products of combustion or of partial combustion.

VI. Pneumonia.-Produced in a similar manner to bronchitis
VII. Tetanus.

VIII. Erysipelas.

IX. Gangrene, pyæmia, and exhaustion.

Recent observations in connection with early death from burns and scalds tend to demonstrate that the fatal event is caused by destruction of, or by interference with, the function of the red blood corpuscles by the heat. Probably the altered red corpuscles cling together, and to the walls of the smaller vessels, and so cause blocking of them by thrombosis. Salvioli1 believes that the blood-plates, affected by the heat, produce minute thrombi by depositing themselves on the walls of the vessels, and that these minute thrombi, becoming subsequently

Arch. per le Scienze Mediche, 1891.