degeneration, not only in the direction of the original diathesis, but also towards instability of the nervous system. The objection to the marriage of blood relations does not rise from the bare fact of their relationship, but has its ground in the fear of their having similar vitiations in their constitution, which, in their children, are prone to become intensified. There is sufficient evidence adducible to prove that close breeding is productive of degeneration; and when the multiform functions of the nervous system are taken into account, it may almost be assumed not only that it suffers concomitantly with other organs, but that it may also be the first to suffer independently.

to Esquirol and Baillarger, it is more frequently transmitted through the female than through the male branch, but this opinion is called in question by Koch of Würtemberg, whose statistics show that hereditary tendency to insanity acts more strongly through the father than through the mother.

CONGENITAL INSANITY.

The morbid mental conditions which fall to be considered under this head are Idiocy (with its modifica tion Imbecility) and Cretinism.

Idiocy.-In treating of idiocy it must be carefully borne in mind that we are dealing with mental phe Of the other causes affecting the parents which ap-nomena disassociated from active bodily disease, and pear to have an influence in engendering a predisposi- that, in whatever degree it may exist, we have to deal tion to insanity in the offspring, the abuse of alcoholic with a brain condition fixed by the pathological circumstimulants and opiates, over-exertion of the mental stances under which its possessor came into the world, faculties, advanced age, and weak health may be cited. or by such as had been present before full cerebral aoGreat stress has been laid on the influence exercised by tivity could be developed, and the symptoms of which the first of these conditions, and many extreme state- are not dependent on the intervention of any subsements have been made regarding it. Such must be quent morbid process. From the earliest ages the term accepted with reserve, for, although there is reason for Amentia has been applied to this condition, in contraattaching considerable weight to the history of ancestral distinction to Dementia, the mental weakness following intemperance as a probable causating influence, it has on acquired insanity. been generally assumed as the proved cause by those who have treated of the subject, without reference to other agencies which may have acted in common with it, or quite independently of it. The question has not as yet been fairly worked out. However unsatisfactory from a scientific point of view it may appear, the general statement must stand-that whatever tends to lower the nervous energy of a parent may modify the development of the progeny. It is merely a matter of probabilities in a given case.

Constitutional tendency to nervous instability once established in a family may make itself felt in various directions, epilepsy, hysteria, hypochondriasis, neuralgia, certain forms of paralysis, insanity, eccentricity. It is asserted that exceptional genius in an individual member is a phenomenal indication.

Confined to the question of insanity, this morbid inheritance may manifest itself in two directions,-in defective brain organization manifest from birth, or from the age at which its faculties are potential, i. e., congenital insanity; or in the neurotic diathesis, which may be present in a brain to all appearance congenitally perfect, and may present itself merely by a tendency to break down under circumstances which would not affect a person of originally healthy constitution.

The causes of congenital idiocy may be divided into four classes:-(1) hereditary predisposition, (2) constitutional conditions of one or both parents affecting the constitution of the infant, (3) injuries of the infant head prior to or at birth, and (4) injuries or diseases affecting the infant head during infancy. All these classes of causes may act in two directions: they may produce either non-development or abnormal development of the cranial bones, as evidenced by microcephalism or by deformity of the head; or they may induce a more subtle morbid condition of the constituent elements of the brain. As a rule, the pathological process is more easily traceable in the case of the last three classes than in the first. For instance, in the case of constitutional conditions of the parents we may have a history of syphilis, a disease which often leaves its traces on the bones of the skull; and in the third case congenital malformation of the brain may be produced by mechanical causes acting on the child in utero, such as attempts to procure abortion, and deformities of the maternal pelvis rendering labor difficult and instrumental interference necessary. In such cases the bones of the skull may be injured; it is only fair, however, to say that more brains are saved than injured by instrumental interference. With regard to the fourth class, it is evident that the term congenital is not strictly applicable; but, as the period of life implicated is that prior to the potentiality of the manifestation of the intellectual powers, and as the result is identical with that of the other classes of causes, it is warrantable to connect it with them, on pathological principles more than as a mere matter of convenience.

In systematic works and in asylum reports, it has been too much the fashion to accept the evidence of the existence of insanity in a relative as a proof of hereditary predisposition in a given case. In estimating the value to be attached to such histories, two things must be taken into acccount,-first, the amount and quality of proved ancestral nervous disease, and, secondly, the period of life at which it appeared in the Dr. Ireland, in his work On Idiocy and Imbecility, alleged insane ancestor. Take, for instance, the case classifies idiots from the standpoint of pathology as folof a lunatic whose father or mother is reported to have lows:-(1) Genetous idiocy: in this form, which he died insane; this may be true in fact, but may still have holds to be complete before birth, he believes the preno bearing on the causation of the patient's insanity; sumption of heredity to be stronger than in other for the parent may have been the subject of mental forms; the vitality of the general system is stated to disease at a period subsequent to the birth of the child, be lower than normal; the palate is vaulted and narhe may have drunk himself into alcoholic mania late row, the teeth misshapen, wrongly placed, and prone in life, or disease of the cerebral arteries in old age may to decay, and the patient dwarfish in appearance; the have produced senile insanity. It is difficult to limit head is generally unsymmetrical and the commissures the remoteness of relationship in tracing hereditary pre- occasionally atrophied; (2) Microcephalic idiocy, a term disposition, mainly from the fact that it frequently which explains itself; (3) Eclampsic idiocy, due to the skips a generation. As a rule it does not confine itself effects of infantile convulsions; (4) Epileptic idiocy; to a single individual of a family, but makes itself felt (5) Hydrocephalic idiocy, due to water on the brain; in one form or another in several members. According (6) Paralytic idiocy, a rare form, due to the brain inIcal Society, in American Journal of Insanity, 1870; G. H. Darwin, form produced by the third class of causes above men1 See Report of Committee appointed by New York State Med-jury causing the paralysis; (7) Traumatic idiocy, a Statistical Society's Journal, June, 1875; Dr. Langdon Down, "On Marriages of Consanguinity," London Hospital Clinical Lectures and Reports, 1866; Dr. Arthur Mitchell, On Consanguineous Marriages," in Edin. Med. Journ., 1865; Maudsley. "On Hereditary Tendency," Journal of Mental Science, Jan., 1863, and Jan., 1864; Trousseau, Clinique Médicale de l'Hôtel de Dieu de Paris, 1868, vol. ii. pp. 129-137: Alfred Henry Huth, The Marriage of Near Kin, 1875.

tioned; (8) Inflammatory idiocy; (9) Idiocy by deprivation of one or more of the special senses. Dr. Ireland's wide experience has enabled him to differentiate these groups further by describing the general charaoteristics, mental and physical, of each.

The general conformation of the idiot is often very | may be safely stated that all idiotic or imbecile children imperfect; he is sometimes deformed, but more fre- have a far better chance of amelioration in asylums dequently the frame is merely awkwardly put together voted to them than by any amount of care and teaching and he is generally of short stature. Only about one- lavished upon them at home. fourth of all idiots have heads smaller than common. Many cases are on record in which the cranial measure-velopment of the intellectual faculties is the prominent ments exceed the average. It is the irregularity of development of the bones of the skull, especially at the base, which marks the condition. Cases, however, often present themselves in which the skull is perfect in form and size. In such the mischief has begun in the brain matter. The palate is very often highly arched, in some cleft; hare-lip is not uncommon; in fact congenital defect or malformation of other organs than the brain is more commonly met with amongst idiots than in the general community. Of the special senses, hearing is most frequently absent. Sight is good, although co-ordination may be defective. Many are mute. On account of the mental dulness it is difficult to determine whether the senses of touch, taste, and smell suffer impairment; but the impression is that their acuteness is below the average. It is needless to attempt a description of the mental phenomena of idiots, which range between utter want of intelligence and mere weakness of intellect.

In the class of idiots just spoken of imperfect defeature, so prominent that it masks the arrest of potentiality of development of the moral sense, the absence of which, even if noticed, is regarded as relatively unimportant; but, in conducting the practical study of congenital idiots, a class presents itself in which the moral sense is wanting or deficient, whilst the intellectual powers are apparently up to the average. It is the custom of writers on the subject to speak of "intellectual" and "moral" idiots. The terms are convenient for clinical purposes, but the two conditions cannot be disassociated, and the terms therefore severally only imply a specially marked deprivation of intellect or moral sense in a given case. The everyday observer has no difficulty in recognizing as a fact that deficiency in receptive capacity is evidence of imperfect cerebral development; but it is not so patent to him that the perception of right and wrong can be compromised through the same cause, or to comprehend that loss of moral sense may result from disease. The same The term Imbecility has been conventionally em- difficulty does not present itself to the pathologist; for, ployed to indicate the less profound degrees of idiocy, in the case of a child born under circumstances adverse but in point of fact no distinct line of demarcation can to brain development, and in whom no process of edube drawn; the application of either term to a given cation can develop an appreciation of what is right or case depends more on the opinion of the observer than wrong, although the intellectual faculties appear to be on the condition of the observed. As the scale of im- but slightly blunted or not blunted at all, he cannot beciles ascends it is found that the condition is evi- avoid connecting the psychical peculiarity with the denced not so much by low obtuseness as by irregu- pathological evidence. The world is apt enough to larity of intellectual development. This serves to mark refer any fault in intellectual development, manifested the difference between the extreme stupidity of the by imperfect receptivity, to a definite physical cause, lowest of the healthy and the highest form of the mor- and is willing to base opinion on comparatively slight bidly deprived type. The two conditions do not merge data; but it is not so ready to accept the theory of a gradually one into the other. Extreme stupidity and pathological implication of the intellectual attributes Bottishness mark many cases of idiocy, but only in the concerned in the perception of the difference between lowest types, where no dubiety of opinion can exist as right and wrong. Were, however, two cases pitted to their nature, and in a manner which can never be one against another-the first, one of so-called intelmistaken for the dulness of the man who is less tal- lectual, the second, one of so-called moral idiocyented than the average of mankind. Where in theory it would be found that, except as regards the psythe morbid (morbid in the sense of deprivation) and chical manifestations, the cases might be identical. the healthy types might be supposed to approach each In both there might be a family history of tendency to other, in practice we find that, in fact, no debatable degeneration of the nervous system, a peculiar cranial ground exists. The uniformity of dulness of the former conformation, a history of nervous symptoms during stands in marked opposition to the irregularity of men- infancy, and of a series of indications of mental incatal conformation in the latter. Comparatively speak-pacities during adolescence, differing only in this, that ing, there are few idiots or imbeciles who are uniformly in the first the prominent indication of mental weakdeprived of mental power; some may be utterly sot-ness was inability to add two and two together, in the tish, living a mere vegetable existence, but every one second the prominent feature was incapacity to distinmust at least have heard of the quaint and crafty say-guish right from wrong. What complicates the quesings of manifest idiots indicating the presence of no mean power of applied observation. In institutions for the treatment of idiots and imbeciles, children are found not only able to read and write, but even capable of applying the simpler rules of arithmetic. A man may possess a very considerable meed of receptive faculty and yet be idiotic in respect of the power of application; he may be physically disabled from relation, and so be manifestly a deprived person, unfit to take a position in the world on the same platform as his fellows.

Dr. Ireland subdivides idiots, for the purposes of education, into five grades,-the first comprising those who can neither speak nor understand speech, the second those who can understand a few easy words, the third those who can speak and can be taught to work, the fourth those who can be taught to read and write, and the fifth those who can read books for themselves. The treatment of idiocy and imbecility consists almost entirely of attention to hygiene, and the building up of the enfeebled constitution, along with endeavors to develop what small amount of faculty exists by patiently applied educational influences. The success which has attended this line of treatment in many of our public and private institutions has been very considerable. It

tion of moral idiocy is, that many of its subjects can, when an abstract proposition is placed before them, answer according to the dictates of morality, which they may have learnt by memory. If asked whether it is right or wrong to lie or steal they will say it is wrong; still, when they themselves are detected in either offence, there is an evident non-recognition of its concrete nature. The question of moral idiocy will always be a moot one between the casuist and the pathologist; but, when the whole natural history of such cases is compared, there are points of differentiation between them and mere moral depravity which must appeal to even biased observers. Family history, individual peculiarities, the manifest imbecility of the acts committed, the general bizarre nature of the phenomena, remove such cases from the ordinary category of crime.

Statistics. According to the census returns of 1871 the total number of persons described as Idiots and Imbeciles in England and Wales was 29,452, the equality of the sexes being remarkable-namely, 14,728 males and 14,724 females. Compared with the entire population, the ratio is one idiot or imbecile to 771 persons, or 13 per 10,000 persons living. Whether the returns are defective, owing to the natural sensitiveness of persons who would desire to conceal the occurrence of idiocy in their families, we have no means

e

of knowing; but such a feeling is no doubt likely to exist healthy climate, and may even be prevented by the
among those who look upon mental infirmity as humil- gravid mother leaving a valley where it is rife for loca
iating, rather than as one of the many physical evils ities where cretinism is unknown. The physical and men-
which afflict humanity. According to Ireland, this num-
ber (29,452) is 25 per cent. below the mark. The follow. tal symptoms of cretinism are so closely allied in essen-
ing table shows the number of idiots according to official tials to those of congenital idiocy as not to demand a
returns of the various countries; probably they are sub- separate description. The marked features of the dis-
ject to the same criticism as the census return for England. ease are its endemic nature and its intimate connection
with goitre. See CRETINISM.

Austria

Hungary..

162

53

140

................

66

58

8424188

65

68

69

Norway.
England and Wales...... 74
Canton of Bern............ 117 Scotland
America.....
79 Ireland
It is difficult to understand the wide divergence of
these figures, except it be that in certain states, such as
Prussia and Bavaria, dements have been taken along with
aments, and in others cretins. This cannot, however, ap:
ply to the case of France, which is stated to have only 66
idiots to every 100 lunatics. In many districts of France
cretinism is very common; it is practically unknown in
England, where the proportion of idiots is stated as higher
than in France; and it is rare in Prussia, which stands at
158 idiots to 100 lunatics. Manifestly imperfect as this
table is, it shows how important an element idiocy is in
social statistics; few are aware that the number of idiots
and that of lunatics approach so nearly.

Bibliography.-Rapport de la Commission de S. M. le Roi de Sardaigne, pour étudier le Crétinisme, Turin, 1848; B. Niépce, Traité du Goltre et du Crétinisme, Paris, 1851; Beobachtungen über den Crétinismus, published by the physicians of the hospital at Mariaberg, Tübingen, 1850, 1851, and 1852; Guggenbühl, Die Cretinen-Heilanstalt auf dem Abendberg, Bern and St. Gall, 1853; Virchow, Untersuchungen über die Entwickelung des Schädelgrundes im gesunden und krankhaften Zustande und über den Einfluss derselben auf Schädelform, Gesichtsbildung, und Gehirnbau (Berlin, 1857), and Gesammte Abhandlungen zur wissenschaftlichen Medicin (Frankfort, 1856); Saint Lager, Études sur les Causes du Crétinisme et du Goltre endémique, Paris, 1867, and Deuxième Série d'Études sur les Causes du Crétinisme, Lyon, 1868; Baillarger, Enquête sur le Goitre et le Crétinisme, Paris, 1873; Max Parchappe, Études sur le Goltre et le Crétinisme, edited and annotated by L. Lunier, Paris, 1874; Lombrosa, Rivista Clinica di Bologna, pt. 7, July, 1873, and pt. 11, November, 1873; Ireland, Edinburgh Medical Journal for August and September, 1875, and On Idiocy and Imbecility, 1877. The lastnamed is the standard work on idiocy.

ACQUIRED INSANITY.

Pathology.

It is predicated in treating of Acquired Insanity that we have to deal with brains congenitally perfect, the exercise of whose functions has been normal until the incidence of disease. A full description of the tissues of the healthy brain will be found in the article ANATOMY (vol. i. pp. 763-773), a careful perusal of which will very materially assist the reader in following the present remarks on pathology. A short recapitulation of certain anatomical facts is, however, necessary. The purely nervous structures of the brain consist of very delicate fibres and cells, the latter occurring only in the gray matter. It is richly supplied Cretinism.-Crétin probably comes from Chrétien, with blood vessels, the supply being six times greater either from the idea that the person was innocent in to the gray matter than to the white. These tissues the sense in which that word is employed occasionally are supported and separated one from the other by a to imply a person who cannot sin, or from the religious connective tissue, or interstitial matter, the neuroglia; respect in which cretins were held. Cretinism is a the whole organ is enveloped in membranes which form of congenital insanity inasmuch as the cretino- separate it from the skull. By one system of independgenetic miasma acts before birth; it is endemic in ent fibres (the expansion system) communication is many mountainous countries, and is said to occur most maintained between the spinal cord, the central ganfrequently on magnesian limestone formations, but glia, and the cortical gray matter; by a second system never at an elevation above 3000 feet. Although all of fibres (the commissural), corresponding and identical cretins have not goitre, and all goitrous persons are not regions of the gray matter of the two opposite hemicretins, there is a very intimate relationship between spheres are united; and by a third system (the horithe two conditions. The districts in Europe in which zontal) communication is maintained between parts of it is most common are the departments of Hautes- the same hemisphere. The cells communicate one Pyrénées, Haute-Savoie, and Hautes-Alpes; Styria, with the other by means of processes or poles, fine Upper Austria, the province of Aosta, and Sardinia. projections from the body of the cell. The observaIt is found more sparsely in other parts of Europe, and tions of Cleland and Boll show that the apical proalso among the Himalayas and Andes. It occasion- cesses become connected with the fibres as they go to the ally presents itself in flat countries,- -a remarkable in- periphery; the basal processes loop with the horizontal stance being the island of Niederwerth below Coblentz, fibres, and also, by means of their recurrent poles, with where out of 750 inhabitants there are 131 cretins (Dr. those of the expansion series. But it is of great importIreland). Notwithstanding the circumscribed area in ance to observe that we have no evidence of fibre comwhich this disease exists, affording, it might be sup- municating directly with fibre, or no certain proof that posed, data founded on the conditions of life common one series of fibres communicates directly with others; to their inhabitants for arriving at conclusions as to its in fact, all anatomical demonstration goes to prove the cause, nothing has been definitely determined. Cre- individuality and isolation of fibre, the processes of the tinism has occupied the attention of many eminent ob- cells being the connecting link. It is universally accepted servers, but the various theories they have advanced that the cerebral cells possess the vital property of genhave been in succession overturned. It has been sug-erating, receiving, and transmitting nervous influences, gested that the condition is due to the constant use of and that the fibres are the organs by means of which these snow water, or to the presence of sulphate of iron or influences are received and communicated. In the words of lime in water, but none of these theories admit of of Herman, "in a part of the central organs (the coruniversal application. That the disease is due to some tical cells) certain material processes are accompanied geological or climatic cause appears certain from the in an inexplicable manner with wholly undefinable phefact, stated by Baillarger, that it disappears from a nomena which characterize what we term consciousness. family in one or two generations after removal to a The term mind may be applied to the combination of

all the actual and possible states of consciousness of the contracting influence of the cells. But if the ex-
the organism. "We have a right to presuppose that citement is unduly prolonged a new result appears;
in the brain, as in other organs of the body, the nor- the cells themselves become exhausted, and therefore,
mal exercise of function is dependent on a perfect even if the stimulus is withdrawn, they are unable to
maintenance of the anatomical relations of the com- assert their ordinary control over the arterial muscular
ponent structures, and conversely that morbid condi- coats in the direction of contraction, so that the in-
tions of these structures must affect the whole economy creased blood supply continues although the stimulus
more or less seriously" (Bucknill and Tuke). In study- which caused it has been removed. Instead of funo-
ing brain pathology it must be kept in view that the tional hyperemia we have a hyperæmia caused, not
brain cannot, like the lungs, liver, and kidneys, cast by functional excitement, but by exhaustion of the
any of its functions on other organs; it must do its own controlling organs. In a minor degree the results of
work, rid itself of its effete matter, and of the products this condition are matters of everyday observation;
of injury or disease, and provide within itself for the over-taxation of the brain functions, by study for
resumption of functions the exercise of which has be- instance, is very generally followed by sensations of
come impaired from whatever cause.
fulness and aching of the head, loss of sleep, and
Solutions of continuity, preventing perfect main-general exhaustion,-a condition which is recovered
tenance of the component cerebral tissues, may arise from when the primary irritation is withdrawn, i.e.,
from-(1) idiopathic causes, i. e., causes originating when the arteries reacquire healthy tone. But if relief
primarily in the brain; (2) traumatic causes (injury to from the causes of irritation is not obtained, a sequence
the head); (3) the effects of other neuroses (morbid of events ensues tending to deterioration of tissue. In
nerve conditions); (4) adventitious products (tumors, the first place, sleep, the condition necessary for rest
etc.); (5) morbid conditions of the general system sec- and recuperation of the cells, becomes unattainable.
ondarily implicating the brain; (6) evolutional condi- Physiological research has shown that during sleep the
tions of the system concurrently affecting the brain; supply of blood to the brain is diminished (anæmia),
(7) toxic agents (poisons). In the case of insanity the that anæmia is necessary for, and hyperemia is inimi-
results of morbid action are confined to the convolu- cal to, its production. Further deterioration of cell
tions of the superior surface of the brain, and to the activity follows on non-recuperation, and concomitant
upper part of its lateral aspects; for the most part its diminished control over the vessels tends to the estab-
base and inferior lateral aspects and the cerebellum are lishment of morbid hyperemia and more or less blood
unaffected. It is true that in old standing cases the stagnation (stasis). It would be far beyond the com-
central ganglia present lesions, but these are for the pass of this article to follow out in detail the various
most part secondary, and are due to the action of dis- pathological processes which ensue on paralysis of vaso-
ease in the superior convolutions.
motor action; two only need be alluded to-(1) the
various changes which take place in the behavior of
the constituents of the blood, producing congestion and
greater or less obstruction to its normal distribution,
and (2) the effects which congestion produces on the
lymphatic system of the brain, the system by which
effete matter is largely removed from it.
It is now
generally recognized that the lymphatics of the brain
are perivascular, ie., that they are tubes surrounding
the arteries, patent under ordinary conditions; when,
however, the arteries are distended, it is easy to com-
prehend that the lymphatic system becomes occluded
by the artery filling up the space provided for it, and
therefore that the removal of waste products becomes
difficult or impossible. It is a pathological axiom that
the structural integrity of a part is dependent on the
maintenance of its vascular unity, in other words, on
the regular supply and withdrawal of blood by its
regular channels. This if impaired or destroyed is
necessarily followed by histological changes and by
disturbance of function.

1. Idiopathic changes occur from disease affecting the tissues, the cause of which it may be impossible to trace, as, for instance, acute inflammation, which, however, is not a frequent cause of insanity. Diffused subacute inflammation is held to be a much more fruitful cause, producing increase (sclerosis) of the neuroglia, degeneration of the cells, destruction (atrophy) and displacement of fibres, and aneurism, distortion, and obliteration of vessels.

A large and important class of causes of idiopathic morbid action is due to over-excitation of the brain. The causes of over-excitation of the brain functions are those which, in most works on insanity, are spoken of as "moral" (grief, anxiety, domestic complications, disappointment, terror, sorrow or joy, religious or political excitement, the exercise of the mental faculties by study unduly prolonged or conducted under adverse circumstances) in contradistinction to "physical" causes, -a distinction which implies some material difference in their method of operation. To the most superficial observer, the deformed head of the idiot, and the paral- By this exposition of a probable sequence of pathoysis of mind and body which follows on the rupture logical events it is desired to indicate that disturbance of a cerebral vessel, are coarsely material conditions; of function directly referable to over-excitation of the but when mental aberration follows on mental excite- brain is not a mere functional derangement, not a mere ment, men are prone to regard it more as a derange-morbid increase of a normal emotion, but that it is the ment of function than as an evidence of deterioration of brain structure. If, however, we give due weight to the results of physiological research, the matter is not quite so obscure. Arguing from the analogies of other organs and from direct observation, there is reason to believe that when the brain functions are being actively exerted there is a dilatation of the vessels and an increased blood supply (hyperæmia) to its superior and lateral surfaces. This functional hypersemia is caused by the direct action of the cerebral cells, which, along with the sympathetic system of nerves, exercise control over the muscular coats of the arteries, the immediate regulators of blood supply to any given part. Control over muscular tissue implies, of course, control in two directions, dilatation and contraction. Functional hyperæmia is in every respect a healthy condition, one necessary for the provision of temporary nutriment during temporary action, ceasing with the withdrawal of stimulus, when the calibre of the vessels is reduced to its original dimensions through

manifestation of a pathological condition, that, in
effect, so-called moral causes may be the producers of
physical cerebral disease. This meets with support
from the clinical observation that, with very rare ex-
ceptions, a considerable period of time elapses between
the incidence of the moral cause and the first indica-
tion of mental alienation,-an interval during which
sleep has been absent in consequence of continued
hyperæmia. Instances of melancholy or mania being
suddenly produced by mental shock must be searched
for in works of fiction. Sudden fright, more especially,
is stated to produce immediate convulsion, epilepsy,
and catalepsy, but not insanity; except in certain com-
paratively rare instances, in which it appears to induce
with great rapidity a cataleptic mental state, presently
to be spoken of as acute primary dementia. Over-
exercise of the intellectual function is not by any means
such a prolific cause of brain disease as undue emotion.
It is not work but worry that kills the brain. When
both are combined the result is often rapid.

On the removal or persistence of congestion depends | connective tissue of the superior convolutions has been the issue of a case-recovery, or further and permanent demonstrated. solution of continuity. Unless relief is soon obtained, the changes in the cells are followed by lesions of other brain structures which are productive of important pathological conditions affecting the general system; these in their turn render recovery more difficult or impossible, or may even cause death. (For a full account of the various lesions found in the brains of the insane, consult Bucknill and Tuke, Manual of Psychological Medicine, 4th ed., cap. vi.; Fox's Pathological Anatomy of the Nervous Centres, London, 1874; J. Batty Tuke, "On the Morbid Histology of the Brain and Spinal Cord as observed in the insane," Brit. and For. Medico-Chirurgical Review, 1873-74.)