MEDICAL JURISPRUDENCE 781 to be by the circulation of unoxygenated blooil through the brain acting as a poison upon .that organ ; and this is attended with all the phenomena of asphyxia, as in suffocation. The phenomena attending asphyxia are as follows. As soon as the oxygen in the arterial blood, through exclusion of air, sinks below the normal, the respiratory movements grow deeper and at the same time more fre quent ; both the inspiratory and expiratory phases are exaggerated, the supplementary respiratory muscles are brought into play, and the breathing becomes hurried. As the blood becomes more and more venous, the respiratory movements continue to increase both in force and frequency. Very soon the expiratory movements become more marked than the inspiratory, and every muscle which can in <iny way assist in expiration is brought into play. The orderly expiratory movements culminate in expiratory convulsions ; these violent efforts speedily exhaust the nervous system, and the convul sions suddenly cease and are followed by a period of calm. The calm is one of exhaustion ; all expiratory active movements have ceased, and all the muscles of the body are flaccid and quiet. But at long intervals lengthened deep inspiratory movements take place ; then these movements become less frequent; the rhythm becomes irregular, so that each breath becomes a more and more prolonged gasp, which becomes at last a convulsive stretching of the whole body ; and with extended limbs and a straightened trunk, with the head thrown back, the mouth widely open, the face drawn, and the nostrils dilated, the last breath is taken. The above phenomena are not all observed except in cases of sudden and entire exclusion of air from the lungs. In slow asphyxia, where the supply of air is gradually diminished (e.g., in drowning), the phenomena are funda mentally the same, but with minor differences. The appearances of the body after death from drowning are various. There may be pallor of the countenance, or this may be livid and swollen. The air passages are filled with frothy mucus, and there may be water in the stomach. The ends of the fingers are often excoriated from grasping at objects ; and weeds, &c., are sometimes found grasped in the hands. The distinction between murder and suicide by drowning can rarely be made out by examination of the body alone, and is usually decided from collateral circumstances or marks of a struggle. Attention must also be paid to the existence of wounds on the body, marks of strangulation on the neck, and the like. (2) Hanging may result in death from asphyxia, or, as is more particularly the case in judicial hanging, some injury is inflicted on the upper portion of the spinal cord, resulting in instant death. The ordinary appearances of death from asphyxia may be found : dark fluid blood, congestion of the brain, intensely congested lungs, the right cavities of the heart full, and the left comparatively empty of blood, and general engorgement of the viscera. Ecchymosis may he found beneath the site of the cord, or a mere parchmenty appear ance. There may even be no mark of the cord visible. The mark, when present, usually follows an oblique course, and is high up the neck. The fact that a body may be suspended after death, and that if this be done speedily whilst the body is still warm there may be a post-mortem mark undistinguishable from the mark observed in death from hanging, must not be forgotten. (3) Suffocation may occur from the impaction of any substance in the glottis, or by covering up the mouth and nose, it is frequently of accidental origin, as when substances become accidentally impacted in the throat, and when infants are overlaid. The pheno mena are those of pure asphyxia, which have already been detailed. On post-mortem examination the surface of the lungs is found covered with minute extravasations of blood, known as punctated ecchymosis. (4) Strangulation may be accomplished by drawing a cord tightly round the neck, or by forcibly compressing the windpipe (throttling). Hence there may be either a circular mark round the neck, not so oblique as after hanging, or the marks of the fingers may be found about the region of the larynx. The cartilaginous structures of the larynx and windpipe may be broken. The mark of the ligature is often low down in the neck. The signs of asphyxia are present in a marked degree. (5) Mephitism. Death from the inhalation of irrespirable gases is a mode of assassination seldom employed, but is frequently resorted to on the Continent by suicides, charcoal fumes being commonly used for the purpose (see POISONS). 6. Death from Starvation. Cases occur in which it is important to distinguish this from other modes of death. In such cases the skin becomes harsh and dry, and may acquire a peculiar odour ; the subcutaneous fat disappears ; tlie gums shrink away from the teeth ; the tongue and mouth become dark-coloured and dry ; the eyes are bloodshot ; the intestines become thin and their coats translucent ; the gall-bladder is distended. The period of total abstinence from food required to kill an adult is unknown, and greatly depends upon whether there be access to liquid. In some cases persons have .been able to subsist on little or no nourishment for long periods, the body being in a state of quasi-hibernation. 7. Death from Extremes of Temperature. (1) Death from cold is not often observed in the British Isles. A portion only of the body, as the extremity of a limb, may perish from extreme cold. After the first sensation of tingling experienced on exposure to severe cold, loss of sensation supervenes, with languor and an irre sistible propensity to sleep. The tendency to this forms nn extreme danger in such cases. (2) Death from extreme heat usually occurs in the form of burning and scalding, attended with destruction of a large, portion of the cutaneous structures. Here the cause of death is obvious. The human body is capable of exposure to very hot air as is seen in Turkish baths for a considerable period with impunity. Sun-stroke is a cerebral affection brought on by too great exposure to a hot atmosphere, especially whilst undergoing fatigue. 8. Death by Lightning. Lightning or an artificial electric current may cause instant death. No visible marks of the effects of the electric current may be left, or the body may be singed or dis coloured, or the skin may be perforated at one or two spots. 9. Wounds. The examination of wounds, whether latal or not, often becomes an important branch of forensic medicine. Wounds are usually divided into contused, lacerated, incised, punctured, and gunshot wounds. For poisoned wounds see POISONS. Each kind of wound requires to be minutely examined and described, as they are in approved works on surgery. The degree of danger from each should be familiar to the medical jurist ; and he should recollect that there is no wound which may not become incidentally fatal from improper treatment, peculiarities of constitution, or accidental inoculation with septic material. Punctured wounds or stabs require minute attention ; for there have been instances in which death has been produced by an instrument so small as a pin thrust into a vital part. Wounds of the head are always dangerous, especially if the blow has been severe. The person so wounded may die without division of the skin, or fracture of the bones, as happens in what is known as concussion of the brain. Contusions which do not divide the skin may fracture the skull ; or the inner table of the skull may be fractured without the outer being broken or depressed. Even wounds of the scalp may prove fatal, from inflammation extending towards the brain. Punctured wounds of the head are more danger ous than cuts, as more likely to excite fatal inflammation. When the brain and its membranes are injured, all such wounds are gene rally fatal. Wounds of the face or organs of sense are often danger ous, always disfiguring, and productive of serious inconvenience. Wounds of the neck are always very serious wherever more than the skin is divided. The danger of opening large blood-vessels, or wounding important nerves, is imminent ; even the division of a large vein in the neck has proved immediately fatal, from the entrance of air into the vessel, and its speedy conveyance to the heart. A blow on the neck has instantly proved fatal, from injury to an important nerve, generally the pneumogastric or the sympathetic. Dislocations and fractures of the bones of the neck prove instantly fatal. Wounds of the chest are always serious when the cavity is penetrated, though persons may recover from wounds of the lungs, and have even survived for some time considerable wounds of the heart. This last is an important fact ; because we are not always to consider the spot where the body of a person killed by a wound of the heart, and apparently remaining where he fell, is found as that in which the fatal wound was inflicted. Instances have occurred of persons surviving severe wounds of the heart for several days. Broken ribs are never without danger : and the same may be said of severe contusions of the chest, from the chance of inflammation extending inwards. Wounds penetrating both sides of the chest arc generally considered as fatal ; but possibly there may be recovery from such. Wounds of the abdomen, when they do not completely penetrate, may be considered as simplewounds, unless when inflicted with great force, so as to bruise the contents of the abdominal cavity ; in that case they may produce death without breach of surface, from rupture of some viscus, as sometimes happens from blows or kicks upon the belly. Wounds injuring the peritoneum are highly perilous, from the risk of severe inflammation. Wounds of the stomach or intestines, or of the gall-bladder, generally prove mortal, from the effusion of their contents into the peritoneal cavity pro ducing fatal inflammation. Wounds of the liver, spleen, or kidneys are generally soon mortal, from the great vascularity of those organs. Wounds of the extremities, when fatal, may generally be con sidered so from excessive haemorrhage, from the consequences of inflammation and gangrene, or from the shock to the system when large portions of the limb are forcibly removed, as in accidents from machinery, and in wounds from firearms. 10. Poisonous Food. Under certain conditions, various articles of diet, especially butcher meat, eggs, milk, butter, cheese, and honey, may become possessed of poisonous properties, and this may arise from a variety of causes besides the introduction of known and specific poisons. Moreover, certain kinds of animal food fish chiefly may have definite toxic properties. Food may be more or less poisonous (1) from unsoundness, either from putridity or decom position or disease ; (2) from the presence of parasites ; (3) from mouldiness, or presence of deleterious microscopic fungi ; and (4) where the flesh is that of animals which have fed on noxious plants, and under this head may also be classed poisonous honey, which bees have gathered from poisonous plants. (5) It may be of tho nature of poisonous fish, using the term fish in the popular sense. (6) Certain fungi or mushrooms are poisonous. Parasitic diseases
would, strictly speaking, come under the first head ; but the pre-