FORENSIC MEDICINE
I.--CRIMES
Forensic medicine is also called Medical Jurisprudence or Legal
Medicine, and includes all questions which bring medical matters into
relation with the law. It deals, therefore, with (1) crimes and (2)
civil injuries.
1. A _crime_ is the voluntary act of a person of sound mind harmful to
others and also unjust. No act is a crime unless it is plainly forbidden
by law. To constitute a crime, two circumstances are necessary to be
proved--(a) that the act has been committed, (b) that a guilty mind or
malice was present. The act may be one of omission or of commission.
Every person who commits a crime may be punished, unless he is under the
age of seven years, is insane, or has been made to commit it under
compulsion.
Crimes are divided into _misdemeanours_ and _felonies_. The distinction
is not very definite, but, as a rule, the former are less serious forms
of crime, and are punishable with a term of imprisonment, generally
under two years; while felonies comprise the more serious charges, as
murder, manslaughter, rape, which involve the capital sentence or long
terms of imprisonment.
An _offence_ is a trivial breach of the criminal law, and is punishable
on summary conviction before a magistrate or justices only, while the
more serious crimes (_indictable offences_) must be tried before a jury.
2. _Civil injuries_ differ from crimes in that the former are
compensated by damages awarded, while the latter are punished; any
person, whether injured or not, may prosecute for a crime, while only
the sufferer can sue for a civil injury. The Crown may remit punishment
for a crime, but not for a civil injury.
II.--MEDICAL EVIDENCE
On being called, the medical witness enters the witness-box and takes
the oath. This is very generally done by uplifting the right hand and
repeating the oath (Scottish form), or by kissing the Bible, or by
making a solemn affirmation.
1. He may be called to give _ordinary evidence_ as a _common witness_.
Thus he may be asked to detail the facts of an accident which he has
observed, and of the inferences he has deduced. This evidence is what
any lay observer might be asked.
2. _Expert Witness._--On the other hand, he may be examined on matters
of a technical or professional character. The medical man then gives
evidence of a skilled or expert nature. He may be asked his opinion on
certain facts narrated--_e.g._, if a certain wound would be immediately
fatal. Again, he may be asked whether he concurs with opinions held by
other medical authorities.
In important cases specialists are often called to give evidence of a
skilled nature. Thus the hospital surgeon, the nerve specialist, or the
mental consultant may be served with a subpoena to appear at court on a
certain date to give evidence. The evidence of such skilled observers
will, it is supposed, carry greater weight with the jury than would the
evidence of an ordinary practitioner.
Skilled witnesses may hear the evidence of ordinary witnesses in regard
to the case in which they are to give evidence, and it is, indeed,
better that they should understand the case thoroughly, but they are not
usually allowed to hear the evidence of other expert witnesses.
In civil cases the medical witness should, previous to the trial, make
an agreement with the solicitor who has called him with reference to the
fee he is to receive. Before consenting to appear as a witness the
practitioner should insist on having all the facts of the case put
before him in writing. In this way only can he decide as to whether in
his opinion the plaintiff or defendant is right as regards the medical
evidence. If summoned by the side on which he thinks the medical
testimony is correct, then it is his duty to consent to appear. If,
however, he is of opinion that the medical evidence is clearly and
correctly on the opposite side, then he ought to refuse to appear and
give evidence; and, indeed, the lawyer would not desire his presence in
the witness-box unless he could uphold the case.
Whether an expert witness who has no personal knowledge of the facts is
bound to attend on a subpoena is a moot point. It would be safer for him
to do so, and to explain to the judge before taking the oath that his
memory has not been sufficiently 'refreshed.' The solicitor, if he
desires his evidence, will probably see that the fee is forthcoming.
A witness may be subjected to _three_ examinations: first, by the party
on whose side he is engaged, which is called the 'examination in chief,'
and in which he affords the basis for the next examination or
'cross-examination' by the opposite side. The third is the
're-examination' by his own side. In the first he merely gives a clear
statement of facts or of his opinions. In the next his testimony is
subjected to rigid examination in order to weaken his previous
statements. In the third he is allowed to clear up any discrepancies in
the cross-examination, but he must not introduce any new matter which
would render him liable to another cross-examination.
The medical witness should answer questions put to him as clearly and as
concisely as possible. He should make his statements in plain and simple
language, avoiding as much as possible technical terms and figurative
expressions, and should not quote authorities in support of his
opinions.
An expert witness when giving evidence may refer to notes for the
purpose of refreshing his memory, but only if the notes were taken by
him at the time when the observations were made, or as soon after as
practicable.
There are various _courts_ in which a medical witness may be called on
to give evidence:
1. =The Coroner's Court.=--When a coroner is informed that the dead body
of a person is lying within his jurisdiction, and that there is
reasonable cause to suspect that such person died either a violent or
unnatural death, or died a sudden death of which the cause is unknown,
he must summon a jury of not less than twelve men to investigate the
matter--in other words, hold an inquest--and if the deceased had
received medical treatment, the coroner may summon the medical attendant
to give evidence. By the Coroners (Emergency Provisions) Act of 1917,
the number of the jury has been cut down to a minimum of seven and a
maximum of eleven men. By the Juries Act of 1918, the coroner has the
power of holding a court without a jury if, in his discretion, it
appears to be unnecessary. In charges of murder, manslaughter, deaths of
prisoners in prison, inmates of asylums or inebriates' homes, or of
infants in nursing homes, he must summon a jury. The coroner may be
satisfied with the evidence as to the cause of a person's death, and may
dispense with an inquest and grant a burial certificate.
Cases are notified to the coroner by the police, parish officer, any
medical practitioner, registrar of deaths, or by any private individual.
Witnesses, having been cited to appear, are examined on oath by the
coroner, who must, in criminal cases at least, take down the evidence in
writing. This is then read over to each witness, who signs it, and this
forms his _deposition_. At the end of each case the coroner sums up, and
the jury return their verdict or _inquisition_, either unanimously or by
a majority.
If this charges any person with murder or manslaughter, he is committed
by the coroner to prison to await trial, or, if not present, the coroner
may issue a warrant for his arrest.
A chemical analysis of the contents of the stomach, etc., in suspected
cases of poisoning is usually done by a special analyst named by the
coroner. If any witness disobeys the summons to attend the inquest, he
renders himself liable to a fine not exceeding £2 2s., but in addition
the coroner may commit him to prison for contempt of court. In criminal
cases the witnesses are bound over to appear at the assizes to give
evidence there. The coroner may give an order for the exhumation of a
body if he thinks the evidence warrants a post-mortem examination.
Coroners' inquests are held in all cases of sudden or violent death,
where the cause of death is not clear; in cases of assault, where death
has taken place immediately or some time afterwards; in cases of
homicide or suicide; where the medical attendant refuses to give a
certificate of death; where the attendants on the deceased have been
culpably negligent; or in certain cases of uncertified deaths.
The medical witness should be very careful in giving evidence before a
coroner. Even though the inquest be held in a coach-house or barn, yet
it has to be remembered it is a court of law. If the case goes on for
trial before a superior court, your deposition made to the coroner forms
the basis of your examination. Any misstatements or discrepancies in
your evidence will be carefully inquired into, and you will make a bad
impression on judge and jury if you modify, retract, or explain away
your evidence as given to the coroner. You had your opportunity of
making any amendments on your evidence when the coroner read over to you
your deposition before you signed it as true.
By the Licensing Act of 1902, an inquest may not be held in any premises
licensed for the sale of intoxicating liquor if other suitable premises
have been provided.
The duties of the coroner are based partly on Common Law, and are also
defined by statute, principally by the Coroners Act of 1887 (50 and 51
Vict. c. 71). They have been modified, however, by subsequent
Acts--_e.g._, the Act of 1892, the Coroners (Emergency Provisions) Act,
1917, and the Juries Act of 1918.
The fee payable to a medical witness for giving evidence at an inquest
is one guinea, with an extra guinea for making a post-mortem examination
and report (in the metropolitan area these fees are doubled). The
coroner must sign the order authorizing the payment, and should an
inquest be adjourned to a later day, no further fee is payable. If the
deceased died in a hospital, infirmary, or lunatic asylum, the medical
witness is not paid any fee. Should a medical witness neglect to make
the post-mortem examination after receiving the order to do so, he is
liable to a fine of £5.
In Scotland the Procurator Fiscal fulfils many of the duties of the
coroner, but he cannot hold a public inquiry. He interrogates the
witnesses privately, and these questions with the answers form the
_precognition_. More serious cases are dealt with by the Sheriff of each
county, and capital charges must be dealt with by the High Court of
Justiciary. In Scotland the verdicts of the jury may be 'guilty,' 'not
guilty,' or 'not proven.'
2. =The Magistrate's Court or Petty Sessions= is also a court of
preliminary inquiry. The prisoner may be dealt with summarily, as, for
example, in minor assault cases, or, if the case is of sufficient
gravity, and the evidence justifies such a course, may be committed for
trial. The fee for a medical witness who resides within three miles of
the court is ten shillings and sixpence; if at a greater distance, one
guinea.
In the Metropolis the prisoner in the first instance is brought before a
magistrate, technically known as the 'beak,' who, in addition to being a
person of great acumen, is a stipendiary, and thus occupies a superior
position to the ordinary 'J.P.,' who is one of the great unpaid. In the
City of London is the Mansion House Justice-Room, presided over by the
Lord Mayor or one of the Aldermen. The prisoner may ultimately be sent
for trial to the Central Criminal Court, known as the Old Bailey, or
elsewhere.
3. =Quarter Sessions.=--These are held every quarter by Justices of the
Peace. All cases can be tried before the sessions except felonies or
cases which involve difficult legal questions. In London this court is
known as the Central Criminal Court, and it also acts as the Assize
Court. In Borough Sessions a barrister known as the _Recorder_ is
appointed as sole judge.
4. =The Assizes= deal with both criminal and civil cases. There is the
_Crown Court_, where criminal cases are tried, and there is the _Civil
Court_, where civil cases are heard. Before a case sent up by a lower
court can be tried by the judge and petty jury, it is investigated by
the _grand jury_, which is composed of superior individuals. If they
find a 'true bill,' the case goes on; but if they 'throw it out,' the
accused is at liberty to take his departure. At the Court of Assize the
prisoner is tried by a jury of twelve. In bringing in the verdict the
jury must be unanimous. If they cannot agree, the case must be retried
before a new jury. At the Assize Court the medical witness gets a guinea
a day, with two shillings extra to pay for his bed and board for every
night he is away from home, with his second-class railway fare, if there
is a second class on the railway by which he travels. If there is no
railway, and he has to walk, he is entitled to threepence a mile for
refreshments both ways.
5. =Court of Criminal Appeal.=--This was established in 1908, and
consists of three judges. A right of appeal may be based (1) solely on a
question of law; (2) on certificate from the judge who tried the
prisoner; (3) on mitigation of sentence.
Speaking generally, in the Superior Courts the fees which may be claimed
by medical men called on to give evidence are a guinea a day if resident
in the town in which the case is tried, and from two to three guineas a
day if resident at a distance from the place of trial, this to include
everything except travelling expenses. The medical witness also receives
a reasonable allowance for hotel and travelling expenses.
If a witness is summoned to appear before two courts at the same time,
he must obey the summons of the higher court. Criminal cases take
precedence of civil.
A medical man has no right to claim privilege as an excuse for not
divulging professional secrets in a court of law, and the less he talks
about professional etiquette the better. Still, in a civil case, if he
were to make an emphatic protest, the matter in all probability would
not be pressed. In a criminal case he would promptly be reminded of the
nature of his oath.
A medical man may be required to furnish a _formal written report_. It
may be the history of a fatal illness or the result of a post-mortem
examination. These reports must be drawn up very carefully, and no
technical terms should be employed.
No witness on being sworn can be compelled to 'kiss the book.' The Oaths
Act (51 and 52 Vict., c. 46, § 5) declares, without any qualification,
that 'if any person to whom an oath is administered desires to swear
with uplifted hand, in the form and manner in which an oath is usually
administered in Scotland, he shall be permitted to do so, and the oath
shall be administered to him in such form and manner without further
question.' The witness takes the oath standing, with the bare right hand
uplifted above the head, the formula being: 'I swear by Almighty God
that I will speak the truth, the whole truth, and nothing but the
truth.' The presiding judge should say the words, and the witness should
repeat them after him. There is no kissing of the book, and the words
'So help me, God,' which occur in the English form, are not employed. It
will be noted that the Scotch form constitutes an oath, and is not an
affirmation. The judge has no right to ask if you object on religious
grounds, or to put any question. He is bound by the provisions of the
Act, and the enactment applies not only to all forms of the witness
oath, whether in civil or criminal courts, or before coroners, but to
every oath which may be lawfully administered either in Great Britain or
Ireland.
A witness engaged to give expert evidence should demand his fee before
going into court, or, at all events, before being sworn.
With regard to notes, these should be made at the time, on the spot, and
may be used by the witness in court as a refresher to the memory, though
not altogether to supply its place. All evidence is made up of
testimony, but all testimony is not evidence. The witness must not
introduce hearsay testimony. In one case only is hearsay evidence
admissible, and that is in the case of a _dying declaration_. This is a
statement made by a dying person as to how his injuries were inflicted.
These declarations are accepted because the law presumes that a dying
man is anxious to speak the truth. But the person must believe that he
is _actually_ on the point of death, with _absolutely_ no hope of
recovery. A statement was rejected because the dying person, in using
the expression 'I have no hope of recovery,' requested that the words
'at present' should be added. If after making the statement the patient
were to say, 'I hope now I shall get better,' it would invalidate the
declaration. To make the declaration admissible as evidence, death must
ensue. If possible, a magistrate should take the dying declaration; but
if he is not available, the medical man, without any suggestions or
comments of his own, should write down the statements made by the dying
person, and see them signed and witnessed. It must be made clear to the
court that at the time of making his statement the witness was under the
full conviction of approaching or impending death.
III.--PERSONAL IDENTITY
It is but seldom that medical evidence is required with regard to the
identification of the living, though it may sometimes be so, as in the
celebrated Tichborne case. The medical man may in such cases be
consulted as to family resemblance, marks on the body, nævi materni,
scars and tattoo marks, or with regard to the organs of generation in
cases of doubtful sex. Tattoo marks may disappear during life; the
brighter colours, as vermilion, as a rule, more readily than those made
with carbon, as Indian ink; after death the colouring-matter may be
found in the proximal glands. If the tattooing is superficial (merely
underneath the cuticle) the marks may possibly be removed by acetic
acid or cantharides, or even by picking out the colouring-matter with a
fine needle. With regard to scars and their permanence, it will be
remembered that scars occasioned by actual loss of substance, or by
wounds healed by granulation, never disappear. The scars of leech-bites,
lancet-wounds, or cupping instruments, may disappear after a lapse of
time. It is difficult, if not impossible, to give any certain or
positive opinion as to the age of a scar; recent scars are pink in
colour; old scars are white and glistening. The cicatrix resulting from
a wound depends upon its situation. Of incised wounds an elliptical
cicatrix is typical, linear being chiefly found between the fingers and
toes. By way of disguise the hair may be dyed black with lead acetate or
nitrate of silver; detected by allowing the hair to grow, or by steeping
some of it in dilute nitric acid, and testing with iodide of potassium
for lead, and hydrochloric acid for silver. The hair may be bleached
with chlorine or peroxide of hydrogen, detected by letting the hair grow
and by its unnatural feeling and the irregularity of the bleaching.
Finger-print impressions are the most trustworthy of all means of
identification. Such a print is obtained by rubbing the pulp of the
finger in lampblack, and then impressing it on a glazed card. The
impression reveals the fine lines which exist at the tips of the
fingers. The arrangement of these lines is special to each person, and
cannot be changed. Hence this method is employed by the police in the
identification of prisoners.
In the determination of cases of doubtful sex in the living, the
following points should be noticed: the size of the penis or clitoris,
and whether perforate or not, the form of the prepuce, the presence or
absence of nymphæ and of testicles or ovaries. Openings must be
carefully sounded as to their communication with bladder or uterus.
After puberty, inquiry should be made as to menstrual or vicarious
discharges, the general development of the body, the growth of hair,
the tone of voice, and the behaviour of the individual towards either
sex.
With regard to the identification of the dead in cases of death by
accident or violence, the medical man's assistance may be called. The
sex of the skeleton, if that only be found, may be judged from the bones
of the female generally being smaller and more slender than those of the
male, by the female thorax being deeper, the costal cartilages longer,
the ilia more expanded, the sacrum flatter and broader, the coccyx
movable and turned back, the tuberosities of the ischia wider apart, the
pubes shallow, and the whole pelvis shallower and with larger outlets.
But of all these signs the only one of any real value is the roundness
of the pubic arch in the female, as compared with the pointed arch in
the male. Before puberty the sex cannot be determined from an
examination of the bones.
Age may be calculated from the presence, nature and number of the
erupted teeth; from the cartilages of the ribs, which gradually ossify
as age advances; from the angle formed by the ramus of the lower jaw
with its body (obtuse in infancy, a right angle in the adult, and again
obtuse in the aged from loss of the teeth); and in the young from the
condition of the epiphyses with regard to their attachment to their
respective shafts.
To determine stature, the whole skeleton should be laid out and
measured, 1-1/2 to 2 inches being allowed for the soft parts.
IV.--EXAMINATION OF PERSONS FOUND DEAD
When a medical man is called to a case of sudden death, he should
carefully note anything likely to throw any light on the cause of death.
He should notice the place where the body was found, the position and
attitude of the body, the soil or surface on which the body lies, the
position of surrounding objects, and the condition of the clothes. He
should also notice if there are any signs of a struggle having taken
place, if the hands are clenched, if the face is distorted, if there has
been foaming at the mouth, and if urine or fæces have been passed
involuntarily. Urine may be drawn off with a catheter and tested for
albumin and sugar.
If required to make a post-mortem examination, every cavity and
important organ of the body must be carefully and minutely examined, the
seat of injury being inspected first.
V.--MODES OF SUDDEN DEATH
There are three modes in which death may occur: (1) Syncope; (2)
asphyxia; (3) coma.
1. =Syncope= is death beginning at the heart--in other words, failure of
circulation. It may arise from--(1) _Anæmia_, or deficiency of blood due
to hæmorrhage, such as occurs in injuries, or from bleeding from the
lungs, stomach, uterus, or other internal organs. (2) _Asthenia_, or
failure of the heart's action, met with in starvation, in exhausting
diseases, such as phthisis, cancer, pernicious anæmia, and Bright's
disease, and in some cases of poisoning--for example, aconite.
The symptoms of syncope are faintness, giddiness, pallor, slow, weak,
and irregular pulse, sighing respiration, insensibility, dilated pupils,
and convulsions.
Post mortem the heart is found empty and contracted. When, however,
there is sudden stoppage of the heart, the right and left cavities
contain blood in the normal quantities, and blood is found in the venæ
cavæ and in the arterial trunks. There is no engorgement of either lungs
or brain.
2. =Asphyxia=, or death beginning at the lungs, may be due to
obstruction of the air-passages from foreign bodies in the larynx,
drowning, suffocation, strangling, and hanging; from injury to the
cervical cord; effusion into the pleuræ, with consequent pressure on the
lungs; embolism of the pulmonary artery; and from spasmodic contraction
of the thoracic and abdominal muscles in strychnine-poisoning.
The symptoms of this condition are fighting for breath, giddiness,
relaxation of the sphincters, and convulsions.
Post mortem, cadaveric lividity is well marked, especially in nose,
lips, ears, etc.; the right cavities of the heart and the venæ cavæ are
found gorged with dark fluid blood. The pulmonary veins, the left
cavities of the heart, and the aorta, are either empty or contain but
little blood. The lungs are dark and engorged with blood, and the lining
of the air-tubes is bright red in colour. Much bloody froth escapes on
cutting into the lungs. Numerous small hæmorrhages (Tardieu's spots) are
found on the surface and in the substance of the internal organs, as
well as in the skin of the neck and face.
3. =Coma=, or death beginning at the brain, may arise from concussion;
compression; cerebral pressure from hæmorrhage and other forms of
apoplexy; blocking of a cerebral artery from embolism; dietetic and
uræmic conditions; and from opium and other narcotic poisons.
The symptoms of this condition are stupor, loss of consciousness, and
stertorous breathing.
The post-mortem signs are congestion of the substance of the brain and
its membranes, with accumulation of the blood in the cavities of the
heart, more on the right side than on the left.
It must be remembered that, owing to the interdependence of all the
vital functions, there is no line of demarcation between the various
modes of death. In all cases of sudden death think of angina pectoris
and the rupture of an aneurism.
The following is a list of some of the commoner causes of sudden death:
(a) =Instantaneously Sudden Death=--
1. Syncope (by far the commonest cause).
2. Aortic incompetence.
3. Rupture of heart.
4. Rupture of a valve.
5. Rupture of aortic aneurism.
6. Embolism of coronary artery.
7. Angina pectoris.
(b) =Less Sudden but Unexpected Death=--
1. Cerebral hæmorrhage or embolism.
2. Mitral and tricuspid valvular lesions if the patient exerts himself.
3. Rupture of a gastric or duodenal ulcer; rupture of liver, spleen, or
extra-uterine gestation, or abdominal aneurism.
4. Suffocation during an epileptic fit; vomited matter or other material
drawn into the trachea or air-passages; croup.
5. Arterio-sclerosis may lead to thrombosis, embolism, or aneurism.
6. Poisoning, as by hydrocyanic acid, cyanide of potassium, inhalation
of carbonic acid or coal gas, oedema of glottis following inhalation of
ammonia.
7. Rapid onset of some acute specific disease, such as pneumonia or
diphtheria; collapse from cholera.
8. Heat-stroke, lightning, shocks of electricity of high tension.
9. Mental or physical shock.
10. Exertion while the stomach is overloaded.
11. Diabetic coma; uræmia.
12. _Status lymphaticus._ This is a general hyperplastic condition of
the lymphatic structures in the body, and is seen in enlargement of
tonsils, thymus, spleen, as well as of Peyer's patches and mesenteric
glands. It is a frequent cause of death during chloroform anæsthesia for
slight operations in young people.
In addition, it may be as well to remember that death sometimes occurs
suddenly in exophthalmic goitre, hypertrophy of the thymus, and in
Addison's disease.
In some cases of sudden death nothing has been found post mortem, even
when the autopsy has been made by skilled observers, and the brain and
cord have been submitted to microscopical examination.
VI.--SIGNS OF DEATH
(1) Cadaveric appearance; ashy white colour. (2) Cessation of the
circulation and respiration, no sound being heard by the stethoscope.
Cessation of the circulation may be determined by (a) placing a ligature
round the base of a finger (Magnus' test); (b) injecting a solution of
fluorescin (Icard's test); (c) looking through the web of the fingers at
a bright light (diaphanous test); (d) the dulling of a steel needle when
thrust into the living body; (e) the clear outline of the dead heart
when viewed in the fluorescent screen. (3) The state of the eye; the
tension is at once lost; iris insensible to light, fundus yellow in
colour; cornea dull and sunken. (4) The state of the skin; pale, livid,
with loss of elasticity. (5) Extinction of muscular irritability. The
above signs afford no means of determining how long life has been
extinct. The following, however, do:
=Cooling of the Body.=--The average internal temperature of the body is
from 98° to 100° F. The time taken in cooling is from fifteen to twenty
hours, but it may be modified by the kind of death, the age of the
person, the presence or absence of clothing on the body, the surrounding
temperature, and the stillness or otherwise of the air about the body.
Still, the body, other things being equal, may be said to be _quite
cold_ in about _twelve hours_.
=Hypostasis= or =post-mortem staining= is due to the settling down of
the blood in the most dependent parts of the body while the body is
cooling. It is a sure sign of death, and occurs in all forms of death,
even in that due to hæmorrhage, although not so marked in degree.
Post-mortem staining (_cadaveric lividity_) begins to appear in from
eight to twelve hours after death, and its position on the body will
help to determine the length of time the body has lain in the position
in which it was found. The staining is of a dull red or slaty blue
colour. It must be distinguished from ecchymosis the result of a bruise,
by making an incision into the part; in the case of hypostasis a few
small bloody points of divided arteries will be seen, in the case of
ecchymosis the subcutaneous tissues are infiltrated with blood-clot.
Internally, hypostasis must not be mistaken for congestion of the brain
or lungs, or the results of inflammation of the intestines. If the
intestine is pulled straight, inflammatory redness is continuous,
hypostasis is disconnected. About the neck hypostasis must not be
mistaken for the mark of a cord or other ligature. When the blood is of
a bright red colour after death (as happens in poisoning by CO or HCN,
or in death from cold), the hypostasis is bright red also.
=Cadaveric Rigidity--Rigor Mortis.=--For some time after death the
muscles continue to contract under stimuli. When this irritability
ceases--and it seldom exceeds two hours--rigidity and hardening sets in,
and in _all_ cases precedes putrefaction. It is caused by the
coagulation of the muscle plasma. It commences in the muscles of the
back of the neck and lower jaw, and then passes into the muscles of the
face, front of the neck, chest, upper extremities, and lastly to the
lower extremities.
It has been noticed in the new-born infant, as well as in the foetus. It
lasts from sixteen to twenty hours or more. In lingering diseases, after
violent exertion, and in warm climates, it sets in quickly, and
disappears in two or three hours; in those who are in perfect health and
die from accident or asphyxia, it may not come on until from ten to
twenty-four hours, and may last three or four days. After death from
convulsions or strychnine-poisoning, the body may pass at once into
rigor mortis. Rigor mortis must be distinguished from _cadaveric spasm_
or the _death clutch_; in the former, articles in the hands are readily
removable, in the latter this is not the case. In tetanic spasm the
limbs when bent return to their former position; not so in rigor mortis.
=Putrefaction= appears in from one to three days after death, as a
greenish-blue discoloration of the abdomen; in the drowned, over the
head and face. This increases, becomes darker and more general, a strong
putrefactive odour is developed, the thorax and abdomen become distended
with gas, and the epidermis peels off. The muscles then become pulpy,
and assume a dark greenish colour, the whole body at length becoming
changed into a soft, semi-fluid mass. The organ first showing the
putrefactive change is the trachea; that which resists putrefaction
longest is the uterus. These putrefactive changes are modified by the
fat or lean condition of the body, the temperature (putrefaction taking
place more rapidly in summer than in winter), access of air, the period,
place, mode of interment, age, etc. Bodies which remain in water putrefy
more slowly than those in air.
=Saponification.=--In bodies which are very fat and have lain in water
or moist soil for from one to three years this process takes place, the
fat uniting with the ammonia given off by the decomposition to form
_adipocere_. This consists of a margarate or stearate of ammonium with
lime, oxide of iron, potash, certain fatty acids, and a yellowish
odorous matter. It has a fatty, unctuous feel, is either pure white or
pale yellow, with an odour of decayed cheese. Small portions of the body
may show signs of this change in six weeks.
=Post-Mortem Examination.=--Never make an autopsy in criminal cases
without a written order from the coroner or Procurator Fiscal. If
authorized, however, first have the body identified, then photographed
if it has not been identified. A medical man representing the accused
may be present, but only by consent of the Crown authorities or of the
Sheriff. Clothing should be examined for blood-stains, cuts, etc.
Examine external surface of body and take accurate measurements of
wounds, marks, deformities, tattooings; note degree and distribution of
post-mortem staining, rigidity, etc.
Examine brain by making incision from ear to ear across vertex, reflect
scalp forwards and backwards, and saw off calvarium. Examine brain
carefully externally and on section.
Examine organs of chest and abdomen through an incision made from
symphysis menti to pubis, reflecting tissues from chest wall and cutting
through costal cartilages.
In cases of suspected poisoning have several clean jars into which you
place the stomach with contents, intestines with contents, piece of
liver, kidney, spleen, etc., and seal each up carefully, attaching label
with name of deceased, date, and contained organs, and transmit these
personally to the analyst.
=Exhumation.=--A body which has been buried cannot be exhumed without an
order from a coroner, fiscal, or from the Home Secretary. There is no
legal limit in England as to when a body may be exhumed; in Scotland,
however, if an interval of twenty years has elapsed, an accused person
cannot be prosecuted (_prescription of crime_).
VII.--DEATH FROM ANÆSTHETICS, ETC.
The coroner in England and Wales and Ireland must inquire into every
case of death during the administration of an anæsthetic. The
anæsthetist has to appear at the inquest, and must answer a long series
of questions relative to the administration of the drug.
Before, therefore, giving an anæsthetic, and so as to furnish yourself
with a proper defence in the event of death occurring, you ought to
examine the heart, lungs, and kidneys of the patient to see if they are
healthy. Should a fatal result follow, the anæsthetist will require to
prove that it was necessary to give the anæsthetic, that the one
employed was the most suitable, that the patient was in a fit state of
health to have it administered, that it was given skilfully and in
moderate amount, that he had the usual remedies at hand in case of
failure of the heart or lungs, and that he employed every means in his
power to resuscitate the patient.
The condition of the lungs is of more importance than the state of the
heart.
The chloroformist ought always to use the best chloroform.
An anæsthetic should never be administered except in the presence of a
_third person_. This applies especially to dentists who give gas to
females.
=Malpractice.=--In every case where a medical man attends a patient, he
must give him that amount of care, skill, knowledge, or judgment, that
the law expects of him. If he does not, then the charge of malpractice
may be brought against him. It is most frequently alleged in connection
with surgical affections--_e.g._, overlooking a fracture or dislocation.
Before a major operation is performed, it is well to get a written
agreement.
VIII.--PRESUMPTION OF DEATH; SURVIVORSHIP
=Presumption of Death.=--If a person be unheard of for seven years, the
court may, on application by the nearest relative, presume death to have
taken place. If, however, it can be shown that in all probability death
had occurred in a certain accident or shipwreck, the decree may be made
much earlier.
=Presumption of Survivorship.=--When two or more related persons perish
in a common accident, it may be necessary, in order to decide questions
of succession, to determine which of them died first. It is generally
accepted that the stronger and more vigorous will survive longest.
IX.--ASSAULT, MURDER, MANSLAUGHTER, ETC.
=Assault.=--This is an attempt or offer to do violence to another
person; it is not necessary that actual injury has been done, but evil
intention must be proved. When a corporal hurt has been sustained, then
_assault and battery_ has been committed. The assault may be aggravated
by the use of weapons, etc.
=Homicide= may be _justifiable_, as in the case of judicial execution,
or _excusable_, as in defence of one's family or property.
_Felonious homicide_ is murder. This means that a human being has been
killed by another maliciously and deliberately or with reckless
disregard of consequences.
=Manslaughter= or =Culpable Homicide= (Scotland) is the unlawful killing
of a human being without malice--as homicide after great provocation;
signalman who allows a train to pass, and so collide with another in
front.
X.--WOUNDS AND MECHANICAL INJURIES
A wound may be defined as a 'breach of continuity in the structures of
the body, whether external or internal, suddenly occasioned by
mechanical violence.' The law does not define 'a wound,' but the _true
skin must be broken_. Wounds are dangerous from shock, hæmorrhage, from
the supervention of crysipelas or pyæmia, and from _malum regimen_ on
the part of the patient or surgeon. _Is the wound dangerous to life?_
This question can only be answered by a full consideration of all the
circumstances of the case; a guarded prognosis is wise in all cases.
=Burns= are caused by flames, highly heated solids, or very cold solids,
as solid carbonic acid; scalds, by steam or hot fluids. Burns may cause
death from shock, suffocation, oedema glottidis, inflammation of serous
surfaces, bronchitis, pneumonia, duodenal ulcer, coma, or exhaustion. A
burn of the skin inflicted during life is followed by a bleb containing
serum; the edges of this blister are bright red, and the base, seen
after removing the cuticle, is red and inflamed; if sustained after
death, a bleb, if present, contains but little fluid, and there are no
signs of vital reaction. There are six degrees of burns: (1) Superficial
inflammation; (2) formation of vesicles; (3) destruction of superficial
layer of skin; (4) destruction of cellular tissue; (5) deep parts
charred; (6) carbonization of bones.
The larger the area of skin burnt, the more grave is the prognosis.
Burns of the abdomen and genital organs are especially dangerous. Young
children are specially liable to die after burns.
XI.--CONTUSED WOUNDS AND INJURIES UNACCOMPANIED BY SOLUTION OF
CONTINUITY
If a blow be inflicted with a blunt instrument, there is produced a
bruise, or _ecchymosis_, of which it is unnecessary here to describe the
appearance and progress. A bruise may be distinguished from a
post-mortem stain by the cuticle in the former often being abraded and
raised. When an incision is made into the bruise, the whole of the
subcutaneous tissues are found to be infiltrated with blood-clot, and
there is no clear margin. In the case of a post-mortem stain the edges
are sharply defined, not raised, and, on section, mere bloody points
are seen which are the cut ends of the divided blood vessels.
XII.--INCISED WOUNDS AND THOSE ACCOMPANIED BY SOLUTION OF CONTINUITY
These comprise incised, punctured, and lacerated wounds. In a recent
incised wound inflicted during life there is copious hæmorrhage, the
cellular tissue is filled with blood, the edges of the wound gape and
are everted, and the cavity of the wound is filled with coagula.
Lacerated wounds combine the characters of incised and contused wounds.
They are caused by falls, being ridden over, machinery crushes, bites,
blows from blunt weapons, etc. The wounds heal by suppuration.
_Punctured wounds_ come intermediate between incised and lacerated. They
are greater in depth than in length, being caused by sword or rapier
thrusts. They cause little hæmorrhage externally, but death may be due
to internal hæmorrhage. They may be complicated by (1) the introduction
of septic material adhering to the instrument; (2) the entrance of
foreign bodies which lodge in the wound, not only carrying in septic
matter, but acting as mechanical irritants; (3) injury to deeper parts,
which may at the time be difficult to detect.
An apparently _incised wound_ may be produced by a hard, blunt weapon
over a bone--_e.g._, shin or cranium. It is often difficult to
distinguish between a wound of the scalp inflicted with a knife and one
made by a blow with a stick. A puncture with a sharp-edged, pointed
knife leaves a fusiform or spindle-shaped wound. A wound from a blow
with a stick might be of this character, or it might present a jagged,
swollen appearance at the margin, with much contusion of the surrounding
tissues. If the wound is seen soon after it is inflicted, examination
with a lens may disclose irregularities of the margins, or little
bridges of connective tissue or vessels running across the wound, and
so be inconsistent with its production by a cutting instrument.
_Lacerated wounds_ as a rule bleed less freely than those which are
incised. Symptoms of concussion would favour the theory of the injury
having been inflicted by a heavy instrument. Again, it is often
difficult to decide whether the injury which caused death was the result
of a blow or a fall. A heavy blow with a stick may at once cause fatal
effusion of blood, but this might equally result from fracture of the
skull resulting from a fall. The wound should be carefully examined for
foreign bodies, such as grit, dirt, or sand. The distinction between
incised wounds inflicted during life and after death is found in the
fact that a wound inflicted during life presents the appearances already
described, whereas in a post-mortem incised wound only a small quantity
of liquid venous blood is effused; the edges are close, yielding,
inelastic; the blood is not effused into the cellular tissue, and there
are no signs of vital reaction. The presence of inflammatory reaction or
pus shows that the wound must have been inflicted some time before
death, probably two or three days.
_Self-inflicted wounds_ are made by the person himself in order to
divert suspicion, or in order to bring accusation against another. Such
wounds are always in front, not over vital organs, and superficial in
character. Note the condition of the clothes in such cases.
XIII.--GUNSHOT WOUNDS
These may be punctured, contused, or lacerated. Round balls make a
larger opening than those which are conical. Small shot fired at a short
distance make one large ragged opening; while at distances greater than
3 feet the shot scatter and there is no central opening. The Lee-Metford
bullet is more destructive than the Mauser. The former is the larger,
but the difference in size is not great. The Martini-Henry bullet
weighs 480 grains, the Lee-Metford 215, and the Mauser 173. Speaking
generally, a gunshot wound, unlike a punctured wound, becomes larger as
it increases in depth; the aperture of entrance is round, clean, with
inverted edges, and that of exit larger, less regular than that of
entrance, and with everted edges.
In the case of high-velocity bullets from smooth-bore rifles, including
the Mauser and Lee-Metford, the aperture of entry is small; the aperture
of exit is slightly larger, and tends to be more slit-like. There is but
little tendency to carry in portions of clothing or septic material, and
the wound heals by first intention, if reasonable precautions be taken.
The external cicatrices finally look very similar to those produced by
bad acne pustules.
The contents of all gunshot wounds should be preserved, as they may be
useful in evidence. A pocket revolver, as a rule, leaves the bullet in
the body.
Wounds inflicted by firearms may be due to accident, homicide, or
suicide. Blackening of the wound, singeing of the hair, scorching of the
skin and clothing, show that the weapon was fired at close quarters,
whilst blackening of the hand points to suicide. Even when the weapon is
fired quite close there may be no blackening of the skin, and the hand
is not always blackened in cases of suicide. Smokeless powder does not
blacken the skin. Wounds on the back of the body are not usually
self-inflicted, but a suicide may elect to blow off the back of his
head. A wound in the back may be met with in a sportsman who indulges in
the careless habit of dragging a loaded gun after him. If a revolver is
found tightly grasped in the hand it is probably a case of suicide,
whilst if it lies lightly in the hand it may be suicide or homicide. If
no weapon is found near the body, it is not conclusive proof that it is
not suicide, for it may have been thrown into a river or pond, or to
some distance and picked up by a passer-by.
A bullet penetrating the skull even from a distance of 3,000 yards may
act as an explosive, scattering the contents in all directions; but the
bullet from a revolver will usually be found in the cranium.
The prognosis depends partly on the extent of the injury and the parts
involved, but there is also risk from secondary hæmorrhage, and from
such complications as pleurisy, pericarditis, and peritonitis. Death may
result from shock, hæmorrhage, injury to brain or important nervous
structures.
XIV.--WOUNDS OF VARIOUS PARTS OF THE BODY
1. =Of the Head.=--Wounds of the scalp are likely to be followed by (1)
erysipelatous inflammation; (2) inflammation of the tendinous
structures, with or without suppuration. A severe blow on the vertex may
cause fracture of the base of the skull. Injuries of the brain include
concussion, compression, wounds, contusion, and inflammation. Concussion
is a common effect of blows or violent shocks, and the symptoms follow
immediately on the accident, death sometimes taking place without
reaction. Compression may be caused by depressed bone or effused blood
(rupture of middle meningeal artery) and serum. The symptoms may come on
suddenly or gradually. Wounds of the brain present very great
difficulties, and vary greatly in their effect, very slight wounds
producing severe symptoms, and _vice versâ_. A person may receive an
injury to the head, recover from the first effects, and then die with
all the symptoms of compression from internal hæmorrhage. This is due to
the fact that the primary syncope arrests the hæmorrhage, which returns
during the subsequent reaction, or on the occurrence of any excitement.
Inflammation of the meninges or brain may follow injuries, not only to
the brain itself, but to the scalp and adjacent parts, as the orbit and
ear. Inflammation does not usually come on at once, but after variable
periods.
2. =Injuries to the Spinal Cord= may be due to concussion, compression
(fracture-dislocation), or wounds. That the wound has penetrated the
meninges is shown by the escape of cerebro-spinal fluid. The cord and
nerves may be injured (1) by the puncture; (2) by extravasation of blood
and the formation of a clot; and (3) by subsequent septic inflammation.
Division or complete compression of the cord at or above the level of
the fourth cervical vertebra is immediately fatal (as happens in
judicial hanging). When the injury is below the fourth, the diaphragm
continues forcibly in action, but the lungs are imperfectly expanded,
and life will not be maintained for more than a day or two. When the
injury is in the dorsal region, there is paralysis of the legs and of
the sphincters of the bladder and rectum, but power is retained in the
arms and the upper intercostal muscles act, the extent of paralysis
depending on the level of the lesion. In injuries to the lumbar region
the legs may be partly paralysed, and the rectal and bladder sphincters
may be involved.
_Railway spine_, or traumatic neurasthenia, may be set up by concussion
of the cord as a result of blows or falls. Passengers after railway
accidents, or miners, often suffer from this affection.
3. =Of the Face.=--These produce great disfigurement and inconvenience,
and there is a risk of injury to the brain. The seventh nerve may be
involved, giving rise to facial paralysis. Punctured wounds of the orbit
are especially dangerous. Wounds apparently confined to the external
parts often conceal deep-seated mischief.
4. =Of the Eye.=--The iris may be injured by sharp blows, as from the
cork of a soda-water bottle. It is usually followed by hæmorrhage into
the anterior chamber, and there may be separation of the iris from its
ciliary border. Wounds at the edge of the cornea are often followed by
prolapse of the iris. Acute traumatic iritis or irido-cyclitis may
supervene four or five days after the injury. The lens is frequently
wounded in addition to the cornea and iris. In dislocation of the lens
into the anterior chamber as the result of a blow, the lens appears like
a large drop of oil lying at the back of the cornea, the margin
exhibiting a brilliant yellow reflex. Partial dislocations of the lens
as the result of severe blows generally terminate in cataract.
5. =Of the Throat.=--Very frequently inflicted by suicides. Division of
the carotid artery is fatal, and of the internal jugular vein very
dangerous on account of entrance of air. Wounds of the larynx and
trachea are not necessarily or immediately dangerous, but septic
pneumonia is very apt to follow. Wounds of the throat inflicted by
suicides are commonly situated at the upper part, involving the hyoid
bone and the thyroid and cricoid cartilages. The larynx is opened, but
the large vessels often escape. In most suicidal wounds of the throat
the direction is from left to right, the incision being slightly
inclined from above downwards. At the termination of a suicidal
cut-throat the skin is the last structure divided, the wound being
shallower as it reaches its termination; the wounds often show
parallelism. The weapon is often firmly grasped in the hand. Inquiry
should be made as to whether the patient is right or left handed, or
ambidextrous.
Homicidal cut throat is usually very severe and situated low down in the
neck or far to the side.
6. =Of the Chest.=--Incised wounds of the walls are not of necessity
dangerous; but severe blows, by causing fracture of the bones and
internal injuries, are often fatal. The symptoms of penetrating wounds
of the chest are--(1) The passage of blood and air through the wound;
(2) hæmoptysis; (3) pneumothorax; and (4) protrusion of the lung forming
a tumour covered with pleura. Fracture of the ribs may be due to direct
violence, as from a blow, when the ends are driven inwards, or to
indirect violence, as from a squeeze in a crowd, when the ends are
driven outwards.
7. =Of the Lungs.=--These usually cause hæmorrhage, and are frequently
followed by pleurisy, either dry or with effusion, and by pneumonia.
8. =Of the Heart.=--Penetrating wounds are fatal from hæmorrhage, of the
base more speedily than of the apex; but life may be prolonged for some
time even after a severe wound to the heart. Injury to the right
ventricle is the most fatal injury and the most frequent. Rupture from
disease usually occurs in the left ventricle; rupture from a crush is
usually towards the base and on the right side.
9. =Of the Aorta and Pulmonary Artery.=--Fatal.
10. =Of the Diaphragm.=--Generally fatal, owing to the severe injury of
the other abdominal organs. If the diaphragm be ruptured, hernia of the
organs may result.
11. =Of the Abdomen.=--Of the walls, may be dangerous from division of
the epigastric artery; ventral hernia may follow, internal hæmorrhage,
etc. Blows on the abdomen are prone to cause death from cardiac
inhibition.
12. =Of the Liver.=--May divide the large vessels. Venous blood flows
profusely from a punctured wound of the liver. Wounds of the
gall-bladder cause effusion of bile and peritoneal inflammation.
Laceration of the liver may result from external violence without
leaving any outward sign of the injury; it is commonly fatal. There is
rapid and acute anæmia from the pouring out of blood into the abdominal
cavity. This may also occur with injuries of other organs in the
abdomen.
13. =Of the Spleen.=--Fatal hæmorrhage may result from penetrating
wounds or from rupture due to kicks, blows, crushes, especially if the
spleen be enlarged.
14. =Of the Stomach.=--May be fatal from shock, from hæmorrhage, from
extravasation of contents, or from inflammation. The danger is
materially lessened by prompt surgical intervention.
15. =Of the Intestines.=--May be fatal in the same way as those of the
stomach. More dangerous in the small than in the large intestines.
16. =Of the Kidneys.=--May prove fatal from hæmorrhage, extravasation of
urine, or inflammation.
17. =Of the Bladder.=--Dangerous from extravasation of urine. In
fracture of the pelvis the bladder is often injured, and extraperitoneal
infiltration of urine occurs, with frequently a fatal issue.
18. =Of Genital Organs.=--Incised wounds of penis may produce fatal
hæmorrhage. Removal of testicles may prove fatal from shock to nervous
system. Wounds of the spermatic cord may be dangerous from hæmorrhage.
Wounds to the vulva are dangerous, owing to hæmorrhage from the large
plexus of veins without valves.
XV.--DETECTION OF BLOOD-STAINS, ETC.
Stains may require detection on clothing, on cutting instruments, on
floors and furniture, etc. The following are the distinctive characters
of blood-stains:
(a) =Ocular Inspection.=--Blood-stains on dark-coloured materials, which
in daylight might be easily overlooked, may be readily detected by the
use of artificial light, as that of a candle, brought near the cloth.
Blood-spots when recent are of a bright red colour if arterial, of a
purple hue if venous, the latter becoming brighter on exposure to the
air. After a few hours blood-stains assume a reddish-brown or chocolate
tint, which they maintain for years. This change is due to the
conversion of hæmoglobin into methæmoglobin, and finally into hæmatin.
The change of colour in warm weather usually occurs in less than
twenty-four hours. The colour is determined, not entirely by the age of
the stain, but is influenced by the presence or absence of impurities
in the air, such as the vapours of sulphurous, sulphuric, and
hydrochloric acids. If recent, a jelly-like material may be seen by the
aid of a magnifying-glass lying between the fibres. If old, a
cinnabar-red streak is seen on drawing a needle across the stain.
(b) =Microscopic Demonstration.=--With the aid of the microscope, blood
may be detected by the presence of the characteristic blood-corpuscles.
The human blood-corpuscle is a non-nucleated, biconcave disc, having a
diameter of about 1/3500 of an inch. All mammalian red corpuscles have
the same shape, except those of the camel, which are oval. The
corpuscles of birds, fishes, reptiles, and amphibians, are oval and
nucleated. The corpuscles of most mammals are smaller than those of man,
but the size of a corpuscle is affected by various circumstances, such
as drying or moisture, so that the medical witness is rarely justified
in going farther than stating whether the stain is that of the blood of
a mammal or not. Unfortunately, the corpuscles are usually so dried that
little information regarding their size can be given.
(c) =Action of Water.=--Water has a solvent action on blood, fresh
stains rapidly dissolving when the material on which they occur is
placed in cold distilled water, forming a bright red solution. The
hæmatin of old stains dissolves very slowly, so employ a weak solution
of ammonia, and this will give a solution of alkaline hæmatin. Rust is
not soluble in water.
(d) =Action of Heat.=--Blood-stains on knives may be removed by heating
the metal, when the blood will peel off, at once distinguishing it from
rust. Should the blood-stain on the metal be long exposed to the air,
rust may be mixed with the blood, when the test will fail. The solution
obtained in water is coagulated by heat, the colour entirely destroyed,
and a flocculent muddy-brown precipitate formed.
(e) =Action of Caustic Potash.=--The solution of blood obtained in water
is boiled, when a coagulum is formed soluble in hot caustic potash, the
solution formed being greenish by transmitted and red by reflected
light.
(f) =Action of Nitric Acid.=--Nitric acid added to a watery solution
produces a whitish-grey precipitate.
(g) =Action of Guaiacum.=--Tincture of guaiacum produces in the watery
solution a reddish-white precipitate of the resin, but on addition of an
aqueous solution of peroxide of hydrogen, or of an ethereal solution of
the same substance (known as _ozonic ether_), a blue or bluish-green
colour is developed. This test is delicate, and succeeds best in dilute
solutions. It is not absolutely indicative of the presence of blood, for
tincture of guaiacum is coloured blue by milk, saliva, and pus.
(h) =Hæmin Crystals (Teichman's Crystals).=--These are produced by
heating a drop of blood, or a watery solution of it, with a minute
crystal of sodium chloride on a glass slide and evaporating to dryness.
A cover-glass is placed over this, and a drop of glacial acetic acid
allowed to run in. It is again heated until bubbles appear. Crystals of
hæmin may now be detected by the microscope. They are dark brown or
yellow rhombic prisms.
An improvement on this test is the use of formic acid alone; on slowly
evaporating it, numerous very small dark crystals are visible if
hæmoglobin has been present (Whitney's test).
(i) =Spectroscopic Appearances.=--If a solution of a recent stain be
examined by the spectroscope, we get two absorption bands situated
between the lines D and E, the one nearer E being doubly as broad as the
other. These bands indicate _oxyhæmoglobin_.
If we now add a little ammonium sulphide to this solution, we get the
spectrum of _reduced hæmoglobin_, which is a single broad absorption
band situated in the interval between the preceding oxyhæmoglobin
bands. By shaking the solution, oxyhæmoglobin is again reproduced, and
gives its special absorption bands.
If ammonia be added to the original solution, _alkaline hæmatin_ is
produced, or if acetic acid be chosen, _acid hæmatin_ is produced, and
each gives its appropriate absorption bands.
_Methæmoglobin_ is formed in stains which have been exposed to the air
for a few days, and _hæmatin_ is found in old stains. _Hæmochromogen_
gives a very characteristic spectrum, and is obtained by reducing
alkaline hæmatin by ammonium sulphide. _Carbon monoxide hæmoglobin_
gives a spectrum which resembles that of oxyhæmoglobin, but it is not
reduced by ammonium sulphide.
(j) =Precipitin Test.=--This allows us to tell whether the blood is from
a human being or not. A specific serum must be obtained from a rabbit
which is sensitized as follows: 10 c.c. of human blood is injected into
its peritoneal cavity at intervals, until from three to five injections
have been given. The serum of this animal's blood will then give a white
precipitate only when brought into contact with dilute solutions of
human blood, but with the blood of no other animal. This is known also
as the 'biologic,' or Uhlenhuth's test.
=Rust Stains.=--These are yellowish-red in colour, and do not stiffen
the cloth. The iron may be dissolved by placing the stain in a dilute
solution of hydrochloric acid, when, on adding ferrocyanide of
potassium, Prussian blue is produced.
=Fruit Stains= are seldom so dark as blood-stains. Solutions of these do
not change colour or coagulate on boiling; ammonia changes the colour to
blue or green; acid brightens the original colour, while chlorine
bleaches it.
=Hairs.=--Human hairs must be identified and distinguished from those of
the lower mammals. If the hair has been pulled out from the root, the
microscope will show that the bulbous root has a concave surface which
fitted over the hair papilla, or that the root is encased in a fatty
sheath.
=Fibres of Clothing.=--Microscopically, wool fibres are coarse, curly,
and striated transversely; cotton fibres appear as flattened bands
twisted into spirals; linen fibres are round, jointed at frequent
intervals, with small root-like filaments; silk fibres are solid,
continuous, and highly glistening.
XVI.--DEATH BY SUFFOCATION
_Signs and Symptoms._--There are usually three stages:
1. Exaggerated respiratory activity; air hunger; anxiety; congested
appearance of face; ringing in ears.
2. Loss of consciousness; convulsions; relaxation of sphincters.
3. Respirations feeble and gasping, and soon cease; convulsions of
stretching character; heart continues to beat for three to four minutes
after breathing ceases.
_Post-Mortem Appearances--External._--Cadaveric lividity well marked;
nose, lips, ears, finger-tips almost black in colour; appearance may be
placid or, if asphyxia has been sudden, the tongue may be protruded and
eyeballs prominent, with much bloody mucus escaping from mouth and nose.
_Internal._--The blood is dark and remains fluid; great engorgement of
venous system, right side of heart, great veins of thorax and abdomen,
liver, spleen, etc. Lungs dark purple in colour; much bloody froth
escapes on squeezing them; mucous lining of trachea and bronchi
congested and bright red in colour; air-cells distended or ruptured;
many small hæmorrhages on surface of lungs and other organs, as well as
in their substance (_Tardieu's spots_), due to rupture of venous
capillaries from increased vascular pressure.
XVII.--DEATH BY HANGING
In hanging, death occurs by asphyxia, as in drowning. Sensibility is
soon lost, and death takes place in four or five minutes. The eyes in
some cases are brilliant and staring, tongue swollen and livid, blood or
bloody froth is found about the mouth and nostrils, and the hands are
clenched. In other cases the countenance is placid, with an almost
entire absence of the signs just given. The mark on the neck, which may
be more or less interrupted by the beard, shows the course of the cord,
which in hanging is obliquely round the neck following the line of the
jaw, but straight round in strangulation. In judicial hanging, death is
not due to asphyxiation, but, owing to the long drop, the cervical
vertebræ are dislocated, and the spinal cord injured so high up that
almost instant death takes place. On dissection the muscles and
ligaments of the windpipe may be found stretched, bruised, or torn, and
the inner coats of the carotid arteries are sometimes found divided. In
ordinary suicidal hanging there may be entire absence of injury to the
soft parts about the neck, the length of the drop modifying these
appearances. The mark of the cord is not a sign of hanging, is a purely
cadaveric phenomenon, and may be produced some hours after death.
XVIII.--DEATH BY STRANGULATION
This differs from hanging in that the body is not suspended. It may be
effected by a ligature round the neck, or by direct pressure on the
windpipe with the hand, in which case death is said to be caused by
_throttling_. Strangulation is frequently suicidal, but may be
accidental. When homicidal, much injury is done to the neck, owing to
the force with which the ligature is drawn. In throttling, the marks of
the finger-nails are found on the neck.
XIX.--DEATH BY DROWNING
Death by drowning occurs when breathing is arrested by watery or
semi-fluid substances--blood, urine, etc. The fluid acts mechanically by
entering the air-cells of the lung and preventing the due oxidation of
the blood. The post-mortem appearances include those usually present in
death by asphyxia, together with the following, peculiar to death by
drowning: Excoriations of the fingers, with sand or mud under the nails;
fragments of plants grasped in the hand; water in the stomach (this is a
vital act, and shows that the person fell into the water alive); fine
froth at the mouth and nostrils; cutis anserina; retraction of penis and
scrotum. On post-mortem examination, the lungs are found to be increased
in size ('ballooned'); on section, froth, water mud, sand, in air-tubes.
The presence of this fine (often blood-stained) froth is the most
characteristic sign of drowning. Froth like that of soap-suds in the
trachea is an indication of a vital act, and must not be mistaken for
the tenacious mucus of bronchitis. The presence of vomited matters in
the trachea and bronchi is a valuable sign of drowning. The blood
collects in the venous system, and is dark and fluid. Tardieu's spots
are not so frequently met with in cases of drowning as in other forms of
asphyxia. The other signs of death by asphyxia are present. Wounds may
be present on the body, due to falling on stakes, injuries from passing
vessels, etc.
The methods of performing artificial respiration in the case of the
apparently drowned are the following (the best and most easily performed
is Schäfer's prone pressure method):
1. _Schäfer's._--Place the patient on his face, with a folded coat under
the lower part of the chest. Unfasten the collar and neckband. Go to
work at once. Kneel over him athwart or on one side facing his head.
Place your hands flat over the lower part of his back, and make
pressure on his ribs on both sides, and throw the weight of your body on
to them so as to squeeze out the air from his chest. Get back into
position at once, but leave your hands as they were. Do this every five
seconds, and get someone to time you with a watch. Keep this going for
half an hour, and when you are tired get someone to relieve you.
Other people may apply hot flannels to the limbs and hot water to the
feet. Hypodermic injections of 1/50 grain of atropine, suprarenal or
pituitary extracts, may be found useful.
2. _Silvester's._--In this method the capacity of the chest is increased
by raising the arms above the head, holding them by the elbows, and thus
dragging upon and elevating the ribs, the chest being emptied by
lowering the arms against the sides of the chest and exerting lateral
pressure on the thorax. The patient is in the supine position--but first
the water must have been drained from the mouth and nose by keeping the
body in the prone position. The tongue must be kept forward by
transfixing with a pin.
3. _Marshall Hall's._--This consists in placing the patient in the prone
position, with a folded coat under the chest, and rolling the body
alternately into the lateral and prone positions.
4. _Howard's._--This consists in emptying the thorax by forcibly
compressing the lower part of the chest; on relaxing the pressure the
chest again fills with air. Here the patient is placed in the supine
position.
The objections to the supine position are that the tongue falls back,
and not only blocks the entrance of air, but prevents the escape of
water, mucus, and froth from the air-passages.
5. _Laborde's Method._--This consists in holding the tongue by means of
a handkerchief, and rhythmically drawing it out fully at the rate of
fifteen times per minute. This excites the respiratory centre, and this
method may be employed along with any of the other methods.
XX.--DEATH FROM STARVATION
The post-mortem appearances in death from starvation are as follows:
There is marked general emaciation; the skin is dry, shrivelled, and
covered with a brown, bad-smelling excretion; the muscles soft,
atrophied, and free from fat; the liver is small, but the gall-bladder
is distended with bile. The heart, lungs, and internal organs are
shrivelled and bloodless. The stomach is sometimes quite healthy; in
other cases it may be collapsed, empty, and ulcerated. The intestines
are also contracted, empty, and translucent.
In the absence of any disease productive of extreme emaciation (_e.g._,
tuberculosis, stricture of oesophagus, diabetes, Addison's disease),
such a state of body will furnish a strong presumption of death by
starvation.
In the case of children there is not always absolute deprivation of
food, but what is supplied is insufficient in quantity or of improper
quality. The defence commonly set up is that the child died either of
marasmus or of tuberculosis.
In cases where it is alleged that a child has been starved and ill-used,
one must examine the body for signs of neglect--_e.g._, dirtiness of
skin and hair, presence of vermin, bruises or skin eruptions. Compare
its weight with a normal child of the same age and sex. If the
disproportion be great and signs of neglect present, then the
probability is great (provided there be no actual disease present) that
the child has been starved.
XXI.--DEATH FROM LIGHTNING AND ELECTRICITY
The signs of death from lightning vary greatly. In some cases there are
no signs; in others the body may be most curiously marked. Wounds of
various characters--contused, lacerated, and punctured--may be
produced. There may be burns, vesications, and ecchymoses; arborescent
markings are not uncommon. The hair may be singed or burnt and the
clothing damaged. Rigor mortis is very rapid in its onset and transient.
Post mortem there are no characteristic signs, but the blood may be dark
in colour and fluid. The presence or absence of a storm may assist the
diagnosis.
Injuries by electrical currents of high pressure are not uncommon;
speaking generally, 1,000 to 2,000 volts will kill. In America, where
electricity is adopted as the official means of destroying criminals,
1,500 volts is regarded as the lethal dose, but there are many instances
of persons having been exposed to higher voltages without bad effects.
The alternating current is supposed to be more fatal than the
continuous. Much depends on whether the contact is good (perspiring
hands or damp clothes). Death has been attributed in these cases to
respiratory arrest or sudden cessation of the heart's action. The best
treatment is artificial respiration, but the inhalation of nitrite of
amyl may prove useful. Rescuers must be careful that they, also, do not
receive a shock. The patient should be handled with india-rubber gloves
or through a blanket thrown over him.
XXII.--DEATH FROM COLD OR HEAT
=Cold.=--The weak, aged, or infants, readily succumb to low
temperatures. The symptoms are increasing lassitude, drowsiness, coma,
with sometimes illusions of sight. Post mortem, bright red patches are
found on the skin surface, and the blood remains fluid for long.
=Heat.=--Death may result from syncope, the result of exposure to great
heat.