SIGNS OF DEATH

Real or Apparent Death

It will be unnecessary here to discuss any of the theories put forward with regard to cases of apparent death or prolonged trance, but simply to note in the order of their occurrence the phenomena which attend real death.

Real Death

Under this heading it is important to draw a distinction between “Somatic death” and “Molecular death.” “Somatic death” is defined as “the cessation of the vital functions and of the general renewal of tissue consequent on that cessation”; “Molecular death” is the death of the tissues themselves.

The signs of death occur as follows:—

1. Entire and continuous cessation of the respiration and circulation; no sounds heard on auscultation. The absence of the heart sounds is the most important sign of death, for even in the severest forms of syncope the cardiac pulsations, as shown by M. Bouchet, can with care be heard.

Tests for cessation of respiration:—

(a) Auscultation. (b) Placing a cold hand-mirror or empty drinking-glass over the mouth or nostrils, or a light feather, and noting the presence or absence of bedewing or movement. (c) Placing a shallow vessel, such as a saucer, full of water on the chest or abdomen, and observing the presence or absence of rippling of the fluid (Winslow‘s test).

Tests for cessation of the circulation:—

(a) Auscultation.

(b) Manual exploration of the principal arteries for pulsation or thrill.

(c) Magnus‘s test, applying a ligature tightly round a finger, sufficient to stop the venous but not the arterial circulation, and noticing whether or not a bloodless ring forms at the seat of ligature, and a zone of livid redness on the distal side of the ligature, the part becoming first red, then purple.

(d) Applying pressure to the finger-nail, and noticing whether the colour disappears on pressure, and a pink tinge appears after relaxing the pressure.

(e) Applying heat, such as dropping melted sealing-wax on the skin, and noting whether or not redness or vesication ensues.

(f) Holding the hand, with the fingers abducted, against a strong fight, and observing whether or not the web of the fingers is translucent.

(g) Inserting a brightly polished needle into a fleshy part of the body, allowing it to remain for ten seconds or so in situ, and noticing whether it is tarnished or not on withdrawing it.

(h) Injecting hypodermically a solution of fluorescin (resorcin-phthalein and sodium bicarbonate, a gramme of each dissolved in 8 c.c. of water). No local discoloration of the skin takes place if the circulation has ceased, but if not, a yellowish-green coloration of the skin occurs round the seat of injection, and the substance may be detected in the blood at a part some distance from the seat of injection. By immersing some white silk threads in the blood drawn at a distance from the prick, then boiling them in distilled water, the latter will have a greenish colour if the fluorescin has been circulated (Icard‘s test).

These tests will detect whether the circulation has ceased or not, and so differentiate suspended animation from real death.

2. The lustre of the eye is lost immediately after death. It has, however, been stated that the iris will respond to the action of atropine and eserine for some hours after death, and that the action of the latter is always more marked than that of the former. The fundus as seen by ophthalmoscopic examination is altered, the normal redness changes to a yellowish-white, the vessels in the disc and just around it become empty, and the veins appear to contain bubbles of gas and the column of blood is broken up (Bouchet). A blackish round or oval stain has been described by M. Larcher on the sclerotic coat on the outer side, which he calls l‘imbibition cadavérique du fond de l‘œil. It is probably due to thinning of the sclerotic from evaporation, enabling the choroid to be seen through it. The spot precedes rigidity and is a forerunner of putrefaction.

3. The most powerful stimulus applied to the body does not cause any reaction. The muscles may, however, be made to contract shortly after death by the stimulus of a slight blow, or by galvanism.

4. The surface of the body becomes of an ashy-white colour.

Exceptions.

(1) Persons of florid complexion retain this on the malar prominence for some time after death.

(2) The red or livid edges of ulcers.

(3) Blue, black, or red tattoo marks, if not effaced during life, do not disappear.—Ecchymoses retain the hue they had at the time of death.

(4) An “icteric” coloration existing at death, as in jaundice, never becomes white.

(5) A rosy tint of the skin on those poisoned by carbon monoxide.

(6) Dusky-red patches in those frozen to death.

(7) In certain cases of drowning, a rosy colour may be observed on the lips and malar prominences.

5. The temperature of the body at the time of death is retained for some time. As a sign of death the fall of temperature must be progressively continuous. Cooling will depend on the medium in which the body is placed, and mere coldness of the body is not a sign of death.

(1) Fat persons retain the heat longer than lean ones; adults longer than children or old persons. Bodies are cooled by—1. Radiation. 2. Conduction. 3. Convection.

(2) Bodies immersed in water cool more rapidly than in air. This fact may be of importance in determining survivorship in a case of drowning.

(3) Bodies in bed and covered by the clothes, or in cesspools and in dung-heaps, cool less rapidly than when exposed.

(4) Persons killed by lightning may keep warm longer than others.

(5) Death by suffocation retards the process of cooling.

(6) The body may be cold externally, but possesses a considerable amount of heat when the internal organs are exposed. Persons who have died of cholera, yellow fever, or suddenly of some acute disease—rheumatism—may retain for some hours a considerable amount of heat. It has even been asserted that in some diseases—cholera—there is an increase of temperature soon after death (Laycock), also after death due to some diseases of the nervous system as in pontine hæmorrhage and cerebro-spinal meningitis, and following prolonged muscular spasm as in tetanus.

(7) Most bodies, under ordinary circumstances, are, as a rule, quite cold in from eight to twelve hours after death. The rate of loss of temperature depends upon the difference between that of the body and its surroundings; it lessens as the body cools. It takes at least twenty-four hours for it to fall to the heat of the surrounding atmosphere.

6. Relaxation, primary flaccidity, more or less general, of the muscular system takes place.

“If the above signs are alone present, death must have taken place in from ten to twelve hours at the longest” (Casper). Exception: cadaveric spasm.

7. Want of elasticity in the eyeball: flaccidity of the iris. This condition invariably occurs in from twelve to eighteen hours after death.

8. Flattening of the muscles of those parts on which the body rests, due probably to loss of vital turgidity.

9. Hypostasis.—Suggillation, or post-mortem staining, is due to the gravitation of the blood to the most dependent parts of the body not subject to direct pressure. The hypostatic marks begin to form in from eight to twelve hours after death, and increase in size till putrefaction sets in. They alter their position with changes in the position of the body so long as the blood remains fluid, but when it has coagulated they remain permanent. Hypostasis may be mistaken for an ecchymosis or a bruise, and in the lungs for congestion, inflammation, &c. Errors may also occur with regard to the brain, stomach, kidneys, and intestines: in the last, the redness of inflammation is seen all over the parts, whereas the coloration of hypostasis is interrupted, and this is best shown by drawing out the convolutions. The heart is an exception to the rule, but it may contain clots varying in size and colour. These are post-mortem formations. The use of the word suggillation is objectionable, as it has been used in opposite senses by Continental and British authors—some writers restricting the term to ecchymosis proper, others using it as synonymous with cadaveric lividity or external hypostasis.

Cutaneous Hypostasis

(1) Meaning of the expression.—The gravitation of the blood in the capillaries after death, in obedience to the laws of inert matter.

(2) On what parts of the body usually seen?—On the most dependent parts of the body; on the whole of the back of the body, if the body be supine. The patches are irregular and slashed, terminate abruptly, and do not fade gradually into the surrounding colourless skin.

(3) At what period after death first observed?—In from eight to twelve hours, gradually extending in size till putrefaction sets in.

(4) Whether or not affected by death from hæmorrhage?—Formed after every kind of death, even after death due to hæmorrhage, although the coloration may not be quite so marked.

(5) Hypostasis is liable to be mistaken for ecchymosis—the result of injury.—Hypostasis must also not be confounded with the livid patches seen on the legs and feet of aged persons and on those who have died from typhus, chronic renal and cardiac disease, &c. The rose patches—“frost erythems”—seen on those who have died from exposure to cold, must not be mistaken for ecchymosis. The above patches are as frequently on the upper surfaces of the body as on the lower, and are not so extended as cadaveric lividities; the blood, moreover, which gives rise to them is diffused through the areolar tissue, and not incorporated with the true skin.

(6) How distinguished from ecchymosis?—Effused or coagulated blood is found when an incision is made in a true ecchymosis, however small, whereas a few bloody points are alone seen on a slight or deep incision into a post-mortem stain or true hypostasis. The seat of hypostasis is the superficial layer of the true skin. Hypostases are never raised above the surface, as ecchymoses sometimes are. In describing these two conditions, “ecchymosis” and “hypostasis,” it is preferable to describe the former as “discoloration from extravasated blood,” and the latter as “lividity after death.”

10. Cadaveric rigidity.—From the moment of death till the time when putrefaction sets in, the muscular structures of the body may be said to pass through three stages:—

(1) Muscular Irritability.—The muscles flaccid, but still possessing the power of contractility on the application of certain stimuli. Parts contracted during the act of dying—cadaveric spasm—as the muscles of the hand grasping a knife or other weapon, may continue so for some time after death.

(2) Cadaveric rigidity.—A state of rigidity, the power of contractility absent.

(3) Commencement of Putrefaction and Chemical Change.—Relaxation again present; all power of contraction lost, not to be regained.

Cadaveric rigidity, or rigor mortis, is a purely muscular phenomenon, and is not dependent on the nervous system, as it is not prevented, though it may be delayed, by division of the nerves, and is as well marked in paralysed as in non-paralysed limbs. Cadaveric rigidity, which occurs early in the heart, must not be mistaken for hypertrophy, or its absence for dilatation. In every case the rigor mortis precedes putrefaction, and consists in a shortening and thickening of certain muscles, chiefly the flexor and adductor muscles of the extremities, and also the elevators of the lower jaw.

This condition commences in the involuntary muscles, and in the heart may simulate hypertrophy of that organ, then passes into the voluntary muscles of the back of the neck and lower jaw, and then into the muscles of the face, front of the neck, chest, and upper extremities, and then into the trunk muscles, and last of all, into those of the lower extremities. In most cases it passes off in the same order, the body becoming quite flaccid, the rigor mortis never returning. These phenomena occur whilst the body is cooling. The muscle becoming rigid is dying, the rigid muscle is dead. The cause of the rigor mortis is held to be due to the coagulation of the myosin. The reaction is acid from the presence of sarcolactic acid, but becomes alkaline during putrefaction.

If fresh difibrinated blood be passed through the rigid muscle, it will become flaccid, and respond by contraction to electric stimulation.

Cadaveric rigidity generally supervenes from eight to twenty hours after death, and may continue from a few hours to four or nine days.

The sooner rigidity comes on after death the sooner will it pass away, and the later the onset the longer it will last. It is a general rule that whatever exhausts the muscular irritability before death causes the early appearance and the more rapid disappearance of rigor mortis.

Conditions which modify the onset and duration of rigor mortis:—

(1) Age.—Transitory rigor mortis may appear in the immature fœtus according to the state of its muscular development.

It is feeble and disappears quickly in infants and young children.

It is usually well marked in adolescents and healthy adults, but feeble in old people.

(2) The Degree of Muscular Development of the Body.—Other things being equal, the greater the muscular development and muscular strength at the time of death, the slower is the onset of rigor mortis, and the longer its duration; the more feeble or exhausted the muscular condition, the more rapid the onset and the shorter its duration.

(3) The Temperature of the Environment of the Body.—In temperate and colder climates rigor mortis follows the usual course. A low temperature, below freezing-point, will retard the onset and favour the duration of rigor mortis, but if the body be suddenly thawed before rigor mortis has set in, it will appear rapidly and disappear more quickly than if it had not been subjected to the process of thawing.

If a body already in a condition of early rigidity be exposed to a temperature of 75° C., the rigidity becomes more marked, since albuminates in the muscles, other than the myosin, become coagulated in addition. This phenomenon has been called heat stiffening.

(4) Mode of Death.—After all exhausting diseases of long or short duration, rigor mortis appears early and passes off quickly, as in death from phthisis, cholera, typhus fever, typhoid, hydrophobia, scurvy, and occasionally in chronic Bright‘s disease.

Death during alcoholic intoxication favours the duration of rigor mortis. After violent muscular exercise death is quickly followed by rigidity. Animals that have been hunted for some time before death stiffen very rapidly. When convulsions precede death, rigor mortis sets in early as a rule, but in certain cases, where death has been preceded by strong convulsions, rigidity may appear quickly, but last for some days, as in some cases of poisoning by strychnine.

Conditions which simulate rigor mortis:—

(1) Stiffening by Catalepsy.—In this condition the temperature of the body will remain at a degree compatible with life over a period incompatible with real death. If a limb be extended and rigid in catalepsy, after passive flexion of it, it will return to its former state.

(2) Rigidity from the Body being Frozen.—In this condition passive movement of the joints is accompanied by crackling due to fracture of their frozen contents.

(3) Heat Stiffening.—Is seen in the bodies of persons who have been suddenly immersed in boiling fluids; also to a certain degree in bodies of persons who have met their death by burning from paraffin lamp accidents.

Cadaveric Spasm or Instantaneous Rigor.—“When this phenomenon occurs the last act of life is crystallised in death.” It is a prolongation of the last vital contraction of the muscles into the rigidity of death. Cadaveric rigidity of the muscles must be distinguished from muscular spasm occurring at the moment of death.

They may thus he distinguished: In cadaveric rigidity any object placed in the hand prior to the onset of rigor mortis can be readily removed, even if the precaution be taken of binding it in the hand prior to the accession of rigor mortis.

In the case of muscular spasm the object is found grasped in the hand, and can only be with difficulty removed.

The difficulty experienced in removing a pistol or other weapon from the hand may point to suicide; its easy removal to homicide, the weapon having been placed there after death.

No adequate explanation of this phenomenon has yet been made. It is not an unusually early onset of rigor mortis in the muscles affected, because they do not share in the initial relaxation that precedes it, or the weapon would fall from the hand, and the bodies would not retain the peculiar attitudes which have been described in different instances. Nothing can simulate cadaveric spasm and it cannot be produced in any way after death. Instantaneous rigor only occurs in cases in which there has been great mental tension and nerve excitation before death. It is a continuation of probably the very last voluntary act of life.

A body showing the signs of death before mentioned (Nos. 1 to 10) may be held to be that of a person who has been dead from two to three days at the longest (Casper).

Muscular states of the body between the period of somatic and molecular death:—

(1) Primary Flaccidity.—The muscles respond to electrical stimuli; the chemical reaction of the muscles is either neutral or faintly alkaline.

(2) Cadaveric Rigidity or Rigor Mortis.—During this condition molecular death takes place; the muscles do not respond to stimuli, but fresh defibrinated blood passed through the muscles will restore the response to stimulation, and their reaction is markedly acid.

(3) Secondary Flaccidity.—Disintegration of the muscular elements takes place, no stimuli will provoke response, and the reaction again becomes alkaline.

Table showing the principal points to be noted in the period of accession of Cadaveric Rigidity and the causes which retard or hasten its appearance, or modify its duration:—

In what does it consist?—In a shortening and thickening of the muscles, particularly the flexors and adductors of the extremities, and elevators of the lower jaw.

Period of Invasion.—Generally in from eight to twenty hours after death. It has been known, however, to supervene within three minutes of death, but it may be delayed for sixteen or seventeen hours.

Period of Duration.—From one to nine days. Three weeks (Taylor).

Order in which the Muscles are affected.—Involuntary muscles, back of neck and lower jaw, muscles of the face, front of the neck, chest, upper extremities and then the lower extremities.

Order in which it disappears.—Back of neck, lower jaw, &c., following the course of its accession.

Effects of Exposure to Cold.—Prolonged by dry cold air, and by cold water.

Effects of Enfeebling Disease prior to Death.—Rapid in its invasion, and passing off rapidly.

Effect of a Robust Frame at Period of Death.—The accession may be prolonged; but, other things being equal, it is more strongly manifested, and continues longer.

Effects of Violent Exercise prior to Death.—Rapidly supervenes and rapidly disappears, as in soldiers killed at the end of a battle.

Effects of Poison.—Poisons which cause violent contractions for some time prior to death—strychnine, &c.—influence the rapid invasion of the rigor mortis, its short duration, rapidly followed by putrefaction. Where death in poisoning by strychnine is almost instantaneous, with a short convulsive stage, rigor mortis comes on rapidly and remains a long time.

11. Putrefaction.—the last of the phenomena which follow death—is the resolution of the organised tissues of the body to the inorganic state. It is a gradual process, and is the result of the action of micro-organisms, aided by moisture, air, and warmth.

Putrefaction is the only absolute sign of death having taken place.

The conditions which modify putrefaction are as follows:—

External Conditions.—1. Micro-organisms; 2. Air; 3. Moisture; 4. Warmth.

Internal Conditions.—1. Age; 2. Sex; 3. Condition of the body—(a) Constitutional peculiarity; (b) State of the body. 4. Kind of death—(a) The result of disease; (b) The result of poisons.

External Conditions Which
Modify Putrefaction

1. Micro-organisms.—A fauna and flora of decomposition has been described in a paper by Hough on “The Fauna of Dead Bodies,” B. M. J., vol. ii. 1897, p. 1853, to which the reader is referred.

Many different forms of micro-organisms combine in the production of putrefaction, and the result of their action is inevitable, unless the body be guarded against their invasion by special means, or the tissues be rendered unfit for their use.

2. Air.—Exposure in the open air has a marked effect in promoting putrefaction; but garments fitting close to the body, and thus excluding air, have a contrary effect. Dry air, or air in motion, by assisting evaporation from the corpse, acts as a preservative. The composition of the soil in which the body is placed has also a more or less modifying effect. In light, porous soil, allowing of the free ingress of air, decomposition is more rapid than in close, compact soil, as clay; but in this we have to contend with another agent—moisture—which more or less counteracts the protective virtue of the closer earth.

3. Moisture.—Putrefaction cannot proceed without moisture. The body, however, contains sufficient water to enable this process to commence spontaneously. Organic substances artificially deprived of water do not putrefy. Cold and heat possess marked antiseptic properties—the former by freezing the fluids in the body, the latter by drying them up.

4. Warmth.—A temperature between 70° and 100° F. is found most favourable to decomposition. The effect of cold is shown by the fact that a body immersed in water during winter, at a temperature between 36° and 45° F., may be so well preserved as to present, ten or twelve days after death, well-marked signs of violence, which would in summer have been utterly obliterated in five or seven days. The preservative influence of cold water will, however, depend greatly on the depth at which the body has been submerged. Bodies so submerged, and then exposed to the air, putrefy with such rapidity that exposure for one day is said to work a greater change than three or four days longer retention of the body in the water. As an instance of the preservative power of cold, may be mentioned the mammoth found in Siberia embedded in a block of ice.

Internal Conditions Which
Modify Putrefaction

1. Age.—The bodies of young children, other things being equal, are said to putrefy rapidly. It should be remembered, however, that clothing possesses considerable power in retarding putrefaction, and that, in the hurry and anxiety to get rid of the infants, they are oftener exposed naked than clothed, which may, in some measure, account for their more rapid decomposition.

2. Sex.—Sex, it would appear, has little or no influence either to retard or hasten putrefaction; but it has been remarked that females dying during or soon after child-birth, irrespectively of the cause of death, putrefy rapidly.

3. Condition of the Body.

(a) Constitutional Peculiarity.—It is generally admitted that persons of the same age and sex, dying similar deaths, and subjected to like conditions as to exposure to the air and interment in the same soil, exhibit marked differences as regards the accession and rapidity of putrefaction. The explanation may be difficult, but the fact still remains.

(b) State of the Body.—Fat and flabby corpses putrefy more rapidly than the lean and emaciated. Hence old people, who are generally thin, keep fresh for a comparatively long time. Bodies, also, which are much mutilated rapidly decompose—decomposition setting in first at the parts injured. In examining wounds and bruises said to have been inflicted during life, it is well to remember that the tendency of putrefaction is to make them appear more severe.

4. Kind of Death.

(a) Effect of Disease.—Healthy persons dying suddenly, other things being equal, are said to decompose more slowly than those who have died from exhausting diseases, as in the case of typhoid, phthisis, and dropsy, following organic disease, or of those diseases attended with more or less putridity of the fluids.

(b) Effects of Poisons.—Putrefaction rapidly supervenes in those who have died suffocated by smoke, by carbonic oxide, and by sulphuretted hydrogen. Narcotic poisoning is stated to accelerate this condition; but in poisoning by phosphorus or alcohol, and in cases of death from sulphuric acid, the putrefactive changes are greatly retarded. Arsenic, chloride of zinc, and antimony are reputed to possess antiseptic properties. The manner in which death takes place from the action of the poison greatly hastens or retards putrefaction. Thus, in the case of poisoning by strychnine, it is found that when death has occurred rapidly, without much muscular exhaustion, putrefaction sets in slowly; but that, when the muscular irritability has been greatly exhausted by successive fits, the contrary is the result.

THE PHENOMENA OF PUTRESCENCE IN
THEIR CHRONOLOGICAL ORDER

1. External

One to Three Days.—Greenish coloration of the abdominal walls. Odour of putrescence is gradually developed, and, concurrently with this, the eyeball becomes soft and yielding to pressure.

Three to Five Days.—The green colour, of a deeper shade, has now passed over the abdomen, extending also to the genital organs. Patches of this green coloration also make their appearance somewhat irregularly on other parts of the body, such as the neck, back, chest, and lower extremities. A dark reddish frothy fluid about this time wells up from the mouth.

Eight to Ten Days.—The patches of green colour have now coalesced, so that the whole body is discoloured. On some parts of the body the colour is of a reddish-green, due to the presence of decomposed blood in the cellular tissue. The abdomen is now distended with gases, the products of decomposition. In India this distension has been known to occur in less than six hours, the average period being a little over eighteen hours. Much depends upon the season of the year. The colour of the eyes has not disappeared, but the cornea have fallen in. Relaxation of the sphincter ani takes place, and the superficial veins appear like reddish-brown cords. The nails still remain firm.

Fourteen to Twenty Days.—The colour of the surface is now bright green, with here and there patches of a blood and brown colour. The epidermal layer of the skin is raised in bullæ of varying size, in some places the skin being more or less stripped off. The nails are detached, and can be easily removed. The hair can be pulled from the scalp with ease. The body is now greatly distended with gases, and the features cannot be recognised, owing to the swollen condition of the face. The body is generally covered with vermin. In determining the time at which death occurred, it will be necessary to take into consideration the season of the year, as it is found that an advanced stage of decomposition may be present in from eight to ten days, with the thermometer ranging between 68° and 77° F., which in winter, with a temperature of from 32° to 50° F., would require twenty to thirty days. “Bodies green from putridity, blown up and excoriated, at the expiry of one month, or from three to five months after death (cæt. par.), cannot with any certainty be distinguished from one another” (Casper).

Three to Six Months.—During the above period the stage of colliquative putrefaction has set in. The thoracic and abdominal cavities, due to the increased formation of gas, have burst. The bones of the cranium have more or less separated, allowing the brain to escape. The soft parts are more or less absorbed, and no recognition of the features is possible. The sex can only be positively made out by the presence of a uterus, or by the peculiar growth of hair on the pubes, which in woman only covers the pubes, but in man extends upwards to the navel.

Saponification.—Bodies exposed to the action of water, or buried in damp, moist soil, are apt to undergo certain changes, in the course of which they become saponified, and the formation of a substance known as adipocere is the result. Adipocere—adeps, lard, and cera, wax—is chiefly composed of margarate of ammonia, together with lime, oxide of iron, potash, certain fatty acids, and a yellow-coloured odorous matter. The melting-point is 126.5° F. Adipocere has a fatty, unctuous feel, is either pure white or of a pale yellowish colour, and with the odour of decayed cheese. It is highly resistant to putrefactive organisms, and is generally free from them. The formation of this substance “to any considerable extent is not likely to occur in less than three to four months in water, or six months in moist earth, though its commencement may take place at a much earlier period” (Casper). The above-quoted authority mentions a case in “which the remains of a fœtus were found imbedded in adipocere, and which fœtus was proved to have been buried in a garden exactly six months and three-quarters.” Taylor also records the case of a bankrupt who committed suicide by drowning, in which the muscles of the buttocks were found converted into adipocere in five weeks and four days at the longest.

Although the above statements may be accepted with regard to the formation of adipocere as far as European countries are concerned, they do not seem to be applicable to India, where the change appears to be more rapid. Dr. S. Coull Mackenzie, in his valuable book on Medico-Legal Experiences in Calcutta, records a case of a young man whose body, recovered after seven days‘ immersion in the river Hooghly, “was found to be in an advanced state of saponification,” and the fleshy portions of undigested food in the stomach were converted entirely into adipocere. “Lastly,” he writes, “in the hot, steamy, rainy months of September and October, in three of the cases above mentioned, saponification was found in bodies immersed in water, both externally and internally, in from two days to eight days ten hours. In the soft and porous soil of Lower Bengal during the rainy seasons, even in a wooden coffin, the change is very rapid—three or four days.”

To explain the formation of adipocere, it has been supposed to be due to the decomposition of the muscular structures of the body, by which hydrogen and nitrogen are evolved, these combining to form ammonia, and this, coming in contact with the fatty acids of the fat, forms a soap. The process of saponification takes place most rapidly in young fat persons; next, in those adults who abound in fat, and in those whose bodies have been exposed to the soil of water-closets; more rapidly in running than in stagnant water; and lastly, in those who have been buried in moist, damp soil, especially if the bodies have been piled one on the top of the other, the lowest being first saponified. The muscular tissue appears to be the first to undergo this change. In water the process is said to be completed in about five months, but in soil a period of two or three years appears necessary.

Mummification is of no medico-legal interest, as the causes which produce it are unknown, and no reliable data can be obtained as to the period of its accession, or the time required for its production.

2. Internal

Table showing the order in which the
Internal Organs undergo Putrefaction: