should not only, as far as practicable, embrace all well-established varieties of mental alienation, but it should, at least, make the attempt to arrange them in groups, according to whatever philosophical idea may exist in the mind of its author. The system adopted may be wrong, it may be artificial and strained, it may lack exactness and sharpness in its boundaries; but, nevertheless, it is better than none, and will at least, by exciting thought in the mind of the reader, lead to discussion, and, perhaps, a better system.

Influenced by these ideas, I venture to propose the following arrangement. It is not claimed that it is perfect; it is not asserted that the several groups are in all cases clearly separated from each other; on the contrary, I know very well that they are not. There are, perhaps, for instance, few if any of the forms which I have classed under the head of "Intellectual Insanities" which do not show emotional disturbance also. I have placed them where they are for the reason that the chief manifestations of mental disorder which they exhibit relate to the intellect. It may be true that not a single one of the forms which are designated as "Emotional Insanities" are not constantly marked by intellectual derangement, but I do contend that their most prominent characteristics are connected with the emotions, and I have classified them in accordance with that view. Similar remarks are applicable to the varieties which I have placed under the head of "Volitional Insanities," though not to the same extent.

The division of "Compound Insanities" embraces those forms which are either so constituted that no predominance of intellectual, emotional, or volitional derangement can be determined, or which manifest themselves in these respects differently with different individuals.

The group of "Constitutional Insanities" comprises those varieties which are either the result of some pre-existing physiological or pathological condition, or which owe their origin to a general toxic state of the system.

Under the head of "Arrest of Mental Development" are placed those states which are due to deficient brain and nervous development.

Relative to the first-named group, "Perceptional Insanities," I have to say that as the perceptions in health form the basis of all higher mental processes, so in mental derangement they are the groundwork on which most of the various forms of

insanity are constructed. That they may be the seat of disorder without the other categories of mental faculties being affected admits of no doubt, and there is hence no good reason why their aberrations should not be included in a classification intended to embrace all well-established forms of mental derangement.

I have not placed such forms as alcoholic mania, malarial mania, absinthine mania, podagral mania, and many others of the kind in this classification, for I do not believe that the cause in such cases exercises any influence as a modificator of the type. Malarial mania, for instance, is not distinguishable, so far as the symptoms are concerned, from the mania produced by alcohol. Moreover, of several cases, for instance, of malarial mania, and many of alcoholic mania, which have come under my observation, some were characterized by mental exaltation, others by mental depression, and others again were well-marked instances of primary dementia. Alcohol, malaria, gout, rheumatism, etc., act as causes, but do not give rise to specific types of insanity.

I. Perceptional Insanities.-Insanities in which there are derangements of one or more of the perceptions.

a. Illusions.

b. Hallucinations.

II. Intellectual Insanities.-Forms in which the chief manifestations of mental disorder relate to the intellect, being of the nature of false conceptions (delusions), or clearly abnormal conceptions.

a. Intellectual monomania with exaltation.

b. Intellectual monomania with depression. c. Chronic intellectual mania.

d. Reasoning mania.

e. Intellectual subjective morbid impulses.

f. Intellectual objective morbid impulses.

III. Emotional Insanities.-Forms in which the mental derangement is chiefly exhibited with regard to the emotions.

a. Emotional monomania.

b. Emotional morbid impulses.

c. Simple melancholia.

d. Melancholia with delirium.

e. Melancholia with stupor.

f. Hypochondriacal mania, or melancholia.

g. Hysterical mania.

h. Epidemic insanity.

IV. Volitional Insanities.-Forms characterized by derangement of the will, either by its abnormal predominance or inertia.

a. Volitional morbid impulses.

b. Aboulomania (paralysis of the will).

V. Compound Insanities.-Forms in which two or more categories of mental faculties are markedly involved.

a. Acute mania.

b. Periodical insanity.

c. Hebephrenia.

d. Circular insanity.

e. Katatonia.

f. Primary dementia.

g. Secondary dementia. h. Senile dementia.

i. General paralysis.

VI. Constitutional Insanities.-Forms which are the result of a pre-existing physiological or pathological condition, or of some specific morbid influence affecting the system.

a. Epileptic insanity.

b. Puerperal insanity.

c. Pellagrous insanity.

d. Choreic insanity, etc.

VII. Arrest of Mental Development.

a. Idiocy.

b. Cretinism.

As each particular form is brought under consideration, the subdivisions of which it is capable will be indicated. This course is not followed now, in order to avoid any possible confusion which might arise from the necessarily intricate construction of the table.

Although arrests of mental development are necessary to be considered in the classification of the several forms of derangement of the mind, it is not the intention to discuss them in the present treatise. The treatment which they require is quite special, and it is such as is not within the province of the medical practitioner, unless he gives himself up to the work and to that alone.

CHAPTER III.

I.

PERCEPTIONAL INSANITIES.

IN uncomplicated perceptional insanities those parts only of the brain are disordered which are concerned in the formation of perceptions. They constitute the primary form of mental aberration, and of themselves are not of such a character as to lessen the responsibility of the individual or to warrant any interference with his rights. They consist entirely of false perceptions; and if the intellect should be for a moment deceived, the error is immediately corrected. As already stated, there are two forms of false perceptions-illusions and hallucinations. In some cases they coexist in the same individual. They may be related to any one or more of the special senses, but are especially common as regards sight and hearing.

a-ILLUSIONS.

Illusions, as already mentioned, are not necessarily due to any central disturbance, though such an origin is common. It is, of course, only when they have such an origin that they are an indication of mental derangement. Thus, it is an illusion if a person, on looking at one object, sees two images, or if, when a single sound strikes the ears, he hears two sounds, and often pitched on different keys. In the first case, the result is due to some cause destroying the parallelism of the visual axes, and may be produced by a tumor of the orbit or by paralysis of one or the other of the ocular muscles. In the latter, it is caused by disease of the middle ear, producing a different degree of pressure upon the fluid in the labyrinth of each ear. A gentleman who has this symptom informs me that at first it was difficult for him to avoid the belief that two persons were talking to him at the same time and saying the same thing, one being a little slower than the other in his speech, and having a voice pitched in a slightly lower key.

Illusions may also result from a combination of circumstances unfavorable to perfect sensation. Thus, when the light is insufficient there may be illusions of the sense of sight. This is especially apt to be the case in the mystifying light of the moon, in which objects are more or less disturbed from

their natural appearance. Under such a condition a roadside bush may appear to be an animal of some kind or other, and a guide-post look like a man on horseback. The state of mind of the individual has great influence in modifying the images which form on the retina, the words which reach the tympanum, the odors which impinge on the Schneiderian membrane, the flavors which touch the tongue, or the objects which come in contact with the tips of the fingers, and this strictly within the limits of health. It is well known that many people, for instance, can see what they wish to see. Falret cites a story, from Fontenelle's "Pluralité des Mondes," of a priest and a young lady talking together in the light of the moon, and examining the lights and shadows on the face of that luminary. "Do they not look to you like cloisters?" said the clergyman. "Oh, no,” she answered, "not in the least; I should rather say like two lovers."

But illusions such as these, and many others that might be mentioned, do not now require consideration. We have rather to give attention to those which, resulting from central derangement, belong to the domain of mental pathology.

Illusions of this character, without the implication of the higher categories of mental faculties, are rare. Still, there is no doubt that they do exist. That is, that there are illusions not the results of derangement of the organs of sense, or of circumstances unfavorable to exact perception, but which are due to a morbid condition of the perceptional ganglia, and the unreal nature of which is clearly recognized by the individual.

Illusions of sight often relate merely to the size of objects. Thus, a young lady who had overtasked herself at school saw everything of enormous size at which she looked. The head of a person seemed to be several feet in diameter, and little children looked like giants. When I took out my watch, while examining her pulse, she remarked that it was as large as the wheel of a carriage. The room in which she sat appeared to her to be several acres in extent. So far as her own person was concerned there were no illusions. Her own hands appeared of the natural size, but, as soon as she turned her eyes to the hands of other people, she at once saw those of enormous proportions. Saurages refers to a somewhat similar case, in which a young woman suffering from epilepsy had the illusion of seeing objects greatly magnified in size. A fly