keep these shades separate from one another. He confounds the past of to-day with the past of yesterday. The extraordinary power of similarity in objects has become useless as a means of recognition. All general terms have disappeared, and in this analysis of decay we may study the synthesis of language and its relations to thought, just as in the dead world of stone we read of the evolution of life and the progress of perfecting humanity. The whole of these impressions have become confused. The order 2001 which is in nature has left it. The world seems crumbling to them. All the most important bonds of thought, such as the indissoluble relation between cause and effect, identity and difference, concrete and abstract, have become friable, or have disappeared. The whole of the intellectual powers have decayed. The individual is no longer able to follow a conversation. He is drifted along by his thoughts, and he scarcely knows what these are. When he speaks, he may use single words-meaningless fragments of sentences. And then may come the last stage of all, that dire, desolate "sans everything."

283. The Delusions of Dements.-Sometimes, however, as a result of the process of the dissociation of ideas, (for all dissociation arises out of defective association,) delusions arise, or illusions haunt the eyes and ears, but they are generally transitory and stupid. "Delusions of suspicion very often arise," says Dr. Crichton Browne, "and these may be either of a definite type or multiform and various. They are much more frequently the latter. This moment the patient fancies that he has been swindled, the next that he has been poisoned, and the next again that he has been beaten and abused. Even the deluslons of the senile dement are dilapidated. Invariably-and this is the important point in diagnosis-they are associated with obvious failure in perception, memory, apprehension, judgment, and depend really, upon errors of sense and reasoning."

2284.

Excitement occurring in Dementia.-Occupations are no longer practiced: the individual is either full of

Op. cit., p. 602.

purposeless restlessness, or remains at rest for hours or weeks, empty of everything. They gaze, but do not see: they have ears, but do not hear. They sit or stand, motionless, cold, like stones-like statues made to depict hideous wrecks of men. Occasionally they will laugh or cry, or mutter meaningless nothings: sometimes they become incoherently eloquent, and pour forth profuse jargon. But it is to be remembered that dementia is liable to be complicated by attacks of excitement, as if even waters could give forth fire. The excitement of dementia may well be thought of in relation to real activity of the brain, as the phosphorence of the sea is thought of in relation to real fire. It is fire which we can wash in; it is fire we can sail in; it is fire in waves instead of flames; it is as if one element had forgotten its nature, and by some strange metamorphosis become another. So it is with the paroxysmal mania which occurs occasionally during the progress of dementia. In this condition, the patient is garrulous to a degree; but it is not with the quickcoming fancies of mania, but with an incoherent harping upon the few and meagre ideas which constitute the shifting intellectual life of the dement.

285. The Emotional Disorders of Dements. It is strange how much the good decays while the bad flourishes. The Devil is always the last to quit the sinking ship. Weakness is possibly not compatible with goodness, and some of those persons who have become noted for their appreciation of character have utterly failed to appreciate this true element of excellence. Mr. Thackeray has made all his good characters stupid! This is surely a mistake in art. So it is that dements are even in later stages of the disease very often irascible and obstinate: they have lost the power of being enthusiastic in a good cause; they could not (207) persevere in well-doing. They are lethargic even in their bad qualities. In this disease, it is not uncommon to find morbid propensities displaying themselves, and these most frequently are manifested in perversions of the sexual appetite. Thus we often find that old, fatuous men make foolish marriages. But for the most part, the disease manifests itself in vague discontent, in querulous anxiety, and in testy fretfulness.

On occasions, however, we have observed a prevailing tone of hilarity and hopefulness. All these mental changes which are manifested in conduct are not without their vestiges in the medium through which conduct becomes actual, the flesh. The eye of a dement is generally dull, and moistened with tears. It is slow in its movements, and gives one the impression of a bull's-eye without the light. The skin is generally pale and dry and wrinkled, the pupils dilated, the expression an empty, uncertain, wandering one. The cheeks are hollow, and the frame generally emaciated. There is an inordinate appetite for food, but the organic functions are not much affected. Dr. Crichton Browne accounts for the peculiar character of the remembrances of dements-for it is observable that they have good memory for long past events, while their reminiscence of recent occurrences is curiously defective-by the fact that in this disease there is a wellmarked dulling of the perception and increasing imperfection in the processes of sensation, as well as the enfeeblement of the conservative powers themselves. This seems to us to be, to a large extent, true. The fact is that memory is always in the direct ratio to attention. If attention is vivid, memory is persistent: if attention is diffused, memories are fugitive. Now, the condition of the dement in this respect is that he holds every thought simply. He cannot concentrate his attention, and therefore he cannot procure any indelible impressions upon memory.

2286. Physical Symptoms of Dementia.-Some of the physical symptoms of dementia have already been noted, but there are one or two of such diagnostic value as to require a more detailed description. No great reliance is to be placed on physiognomical diagnosis, and it is to be remarked as somewhat curious that the facial expression of dements is not by any means adequately indicative of the mental ruin. Many of the early acquired habits of manner remain to the dement. The symptom which is most characteristic is, however, the muscular tremors, which are even more persistent and regular than in general paralysis, and it is to be noted that these affect the hands and arms in the first instance. It has been noted that the convulsive movements of epilepsy or

the explosions of energy discharged from certain parts of the brain, are manifested soonest and with most frequency in those muscles which are most intimately associated with voluntary movements. But in dementia the energy is not discharged like a bullet from a gun, but dribbles like water from a leaking vessel. It is manifested not in convulsions, but in muscular tremors. It is an incontinence, in fact, of energy by the tissues of the brain. Still, as we should expect, even this trickling overflow or leakage runs in the channels of use, and those muscles which are most subservient to voluntary action are those which are soonest and most frequently affected by those tremors. Thus it is that the hands and arms and neck and face are the parts most frequently involved. Use being the ruler of the distribution, it was to be expected that these tremors would occur with greater violence on one side of the body than on the other; and observation has proved that that is actually the case. A very interesting and illustrative case is recorded by Dr. Browne, which is well worth quoting. "A patient who was in this asylum about cighteen months ago afforded a good example of senile trembling of the worst type. He was a sexton from Leeds, and, although only sixty years of age, had the aspect of an extremely old man, and labored under distinct senile dementia. His memory had given way fifteen months before he was brought to this hospital, and had become gradually more and more enfeebled. The calendar was a blank to him, and he could not even be brought to remember the days of the week. His apprehension was slow and imperfect, and his attention could not be fixed. He was restless and ill at ease, for ever wondering where he had got to, and spending most of the night in exploring the four corners of his bedroom. Delusions and hallucinations also distressed him: he was about to die, strange figures gathered round him, and fumes of sulphur invaded his nostrils. Emaciated and haggard, he could not walk about without assistance, his inability to do so being partly owing to weakness, and partly to excessive muscular tremor affecting the whole body, but more decidedly its right half. The shaking continued without intermission throughout his waking hours, and prevented him dressing or feeding himself. When he tried to lift anything,

his hand trembled violently: when he spoke, his head nodded and shook and his features quivered. The grasping power of the hand was weakened, and indeed all the muscles were wasted and enfeebled. This singular muscular agitation, we were informed, came on at the same time with the mental failure, fifteen months prior to his admission here, and was preceded by a peculiar, numb, dead feeling in the right foot. The right side had always been more severely affected than the left. It was noted that the left pupil was considerably larger than the right, and that the patient labored under abnormal thermal sensations. Even in cold weather, he would throw off all the bedclothes except one sheet, and complain that his skin was burning, when it was shown by the thermometer to be only of the normal temperature. Treated by a liberal dietary, by wine and by succus conii, this old man considerably improved. He became composed in mind, and the muscular trembling greatly abated. To the end, however, he was demented and afflicted by tremor." But it must be remembered that you may have dementia complicated with paralysis and other nervous disorders. In the last stages of the disease, epilepsies are by no means uncommon. supervenes: then come muscular twitchings, possibly clonic spasms, passing into the final coma. It may be well to note in this place that the pulse of the senile dement is generally slow, the temperature is always slightly below the normal standard, and the patient almost invariably loses weight.

Coma

287. Distinction between Acute and Chronic Dementia. The first of these is exceedingly rare, so much so that the utility of the distinction has been doubted. When it does exist, it is marked by profound melancholy or stupor. It is more rapid in its progress, and its stages are not so clearly distinguishable from one another. It may be due to fevers, hæmorrhages, metastases, or suppression of the customary evacuations. It is generally the more curable form of this disease, but it may pass into acute mania. It is presumably caused by softening or other chronic disease of brain. Chronic dementia is very common: it is in this form of dementia that we find the incoherence which we have already described. It may result from apoplexy, epilepsy,