a similar result follows the hæmorrhage. Nowadays, in both of these injuries, any well-instructed surgeon will open the head, secure the bleeding vessel, and turn out the clot with a good chance of recovery in a large number of cases. Even gunshot wounds of the brain are no longer necessarily fatal. Among a number of other successful cases one has been recently reported in which the ball went all the way from the forehead to the back of the head, and after striking the bone rebounded into the brain. The back of the skull was opened, the ball removed, and a rubber drainage tube of the calibre of a lead pencil passed in the track of the ball completely through the head, and the patient recovered. So little danger now attaches to opening the skull, with antiseptic precautions similar to those already described, that the latest writer on trephining (Seydel) estimates that trephining per se is fatal only in 1.6 per cent. of the cases. Mr. Horsley has recently published a most remarkable paper, including 10 operations on the brain, in which, without anything on the exterior to indicate its situation, the site of the disease was correctly located in all, and 9 of them recovered after operation.

Almost equally astonishing are the results of brain surgery in certain cases of epilepsy; for the surgical treatment of the cases justifying such interference has been attended with the most brilliant results. In these cases the spasm begins in a particular part of the body; for example, the hand or the thumb, or it is limited to one arm, or to one side of the body. Some of them have been operated upon without any benefit, but a large number of other cases have been operated on and either benefited or, in not a few cases, have been completely restored to health. That the words "brilliant results" are not inappropriate will certainly be granted when we look at Mr. Horsley's table of cases. One patient had 2870 epileptic convulsions in thirteen days, and completely recovered, not only from the operation, but also from his

terrible malady, after the removal of a diseased portion of the brain, the result of an old depressed fracture of the skull. Besides this, a few cases of headache so inveterate as to make ordinary occupations impossible and life itself a burden have been cured by trephining the skull. Even insanity itself has been cured by such an operation in cases in which it has followed injuries to the head. What the ultimate result of these recently inaugurated operations will be it is impossible to tell as yet, but thus far they have been so beneficent and so wonderful as to arouse not only our greatest astonishment, but also our most sanguine hopes.

The question will naturally arise how is it that the neurologists can determine so exactly the location of such tumors, abscesses, hæmorrhages, scars, and other alterations of tissue giving rise to epilepsy and other disorders mentioned, without the slightest indication on the exterior of the skull to point to the diseased spot. That this is of supreme importance in the brain will be evident upon a moment's reflection. In other parts of the body, even if we make an error of an inch or two, it is of comparatively little importance, as the incision can be easily prolonged, and heals readily. But in the skull, from the very nature of the bony envelope, an error of an inch or two means almost certain failure to find the disease, and means, therefore, possibly the death of the patient.

It is impossible within the limit of this paper to state in detail the method, but the following brief sketch may give some idea of it. Whatever can be advanced against vivisection, there is this to be said in its favor, that without it the exact localization of cerebral tumors and other such lesions, which is one of the chief glories of the present day, would be impossible. We owe our knowledge of the location of cerebral functions to many observers, chief of whom are Ferrier and Horsley, of England, and Fritsch, Hitzig, and Goltz, of Germany. Horsley's method will suffice as a type.

The brain of a monkey having been exposed at the part to be investigated, the poles of a battery are applied over squares one-twelfth of an inch in diameter, and all the various movements which occur (if any) are minutely studied. One square having been studied, the next is stimulated, and the results are again noted, and so on from square to square. These movements are then tabulated. For example, all those adjacent squares which, when stimulated, produce movements of the thumb are called the region for representation of the thumb, or, shortly, "the thumb centre"; and to all those squares which produce movements of the hand, the elbow, the shoulder, or the face, etc., are given corresponding names. In this way the brain has been mapped out, region by region, and the same minute, patient study given to each.

These animals, I should add, are etherized so that they do not suffer the least pain. I may also say in passing that such operations, with few exceptions, even without ether, are not painful. The brain itself can be handled, compressed cut, or torn without the least pain. A number of cases have already been reported in which a considerable portion of the human brain has been removed by operation and the patients have been out on the street within a week, without pain, fever, or a single dose of medicine.

Studying in this way the brain of the lower animals, we now have a very fair knowledge of the localization of many of its functions. With the functions of the front part we are as yet not familiar. The part which lies, roughly speaking, behind and in front of one of the chief fissures of the brain (the fissure of Rolando), which runs downward and forward above the ear, is known as the motor region." In this region the different centres have been mapped out in the monkey's brain, and have been verified in the brain of man many times. Most of that part of the brain above and behind the ear has no special functions that we know of at

present, except one region, which is the centre for sight. Injury to this produces blindness of the half of each retina on the same side as the injury to the brain. But it is extremely difficult to obtain in the lower animals any evidence of the special senses other than that of touch, the abolition of which produces loss of feeling, of which we can get exact evidence. Motion and sensation, therefore, are the two things that can be most readily determined.

Having now ascertained in animals the location of the particular centres, the next step is to apply this knowledge to the human brain in judging of the processes of disease. But it will be easily seen that the experiments that disease performs in a human brain are clumsy, spread over a wide area, and therefore often difficult of interpretation. Instances affecting a single little area of brain surface one-twelfth of an inch in diameter are almost unknown, and a tumor has been removed of such size that it produced direct pressure upon more than twelve hundred such squares, and indirectly produced pressure upon many distant parts of the brain. This is, of course, very clumsy experimentation. The familiar game of "shouting proverbs" will well illustrate the difficulty of interpreting the answers of disease to our question, "Where is it located?" Imagine 1200 persons, each assigned a single word of a proverb of 1200 words. At a given signal each shouts his own word. What a Babel of sound! How utterly impossible of disentanglement and proper arrangement! This is the answer of disease as represented by such a tumor. Take each of the 1200 persons in the proper order and question him separately and repeatedly, write down the answers accurately and in their proper sequence, and behold the proverb! This is the answer of scientific investigation as seen in vivisection.

Instead of there being a tumor, a blood-vessel will sometimes break in the brain, and produce a clot, affecting similarly

a large area; or softening of the brain will in the same way invade an equal or a greater number of centres. It is therefore extremely rare that we can find a small area, such as that for speech, or for the hand, or for the arm, or for the face, or for the leg, or for sight, that is involved entirely by itself. But such cases do occasionally occur, and they are extremely valuable in fortifying the conclusions derived from the exact experiments of the laboratory. While some of the cases have introduced confusion and uncertainty from the character of nature's experiments, it can be broadly asserted that generally they have absolutely confirmed them. The results obtained by the surgery of the brain have more than confirmed them; for, as indicated already, the brain has been opened, and that portion which, according to experiment, is believed to be the centre for the wrist, or for the shoulder, etc., has been cut out, and paralysis of the corresponding part (a paralysis which, however, is only temporary) has proved positively the exactness of the inference from animals.

We are still a little uncertain as to the exact functions of large portions of the brain, but we have made a reasonable beginning; we have found firm ground to stand upon, and the results already obtained in the relief of human suffering and the cure of disease are such as readily encourage the hope that in the near future we shall be able to do vastly more. The opponents of vivisection have stoutly contended that it has shown no useful results. Let us wholly ignore the researches of Sir Charles Bell, of Harvey or Hunter, or other experimenters of the past. Here is a field in which the last ten years have opened wholly new ground for modern surgery, in which already the operations of the last four years have been marvellously successful, and have startled even surgeons themselves. Had vivisection done nothing else than this, it would be amply justified, and to obstruct re