GENERAL CONSIDERATIONS.

Before the structure of the brain was understood, Buffon spoke of it as a "mucous substance of no great importance." Its functional significance was so slightly appreciated that some people hardly suspected they had any brains, until an accident revealed their existence. Latterly, however, it is generally understood that the perfection of an animal depends upon the number and the development of the organs controlled by the nervous system, the sovereign power of which is symbolized by a grand cerebrum, the throne of Reason. That animal which is so low in the scale of organization as to resemble a vegetable, belongs to an ascending series ending in man. The lowest species have no conscious perception, and their movements do not necessarily indicate sensation or volition. Instinct culminates in the Articulates, especially in Insects; while created intelligence reaches its acme in man, the highest representative of the Vertebrates.

"All things by regular degrees arise—
From mere existence unto life, from life
To intellectual power; and each degree
Has its peculiar necessary stamp,
Cognizable in forms distinct and lines."—LAVATER.

Man, in the faculties of mind, possesses more than a complement for instinct; some of the lower animals, however, seem to share his rational nature, and to a certain degree become responsible to him. Finally, the manifestations of mind bear a relation to the development of cerebral substance, and to the bodily organization which supplies the brain with blood. Fig. 76 shows the relative amount of brain matter in the lower animals, compared with that of man; the peculiarities of each agreeing with its cerebral conformation. It is easier to measure the capacity of skulls in different races than to procure and weigh their brains. The following table has been published.

Race.CUBIC INCHES.
Swedes,100.00
Anglo-Saxons,96.60
Finns,95.00
Anglo-Americans,94.30
Esquimaux,86.32
North America Indians,84.00
Native Africans,83.70
Mexicans,81.70
American Negros,80.80
Peruvians and Hottentots,75.30
Australians,75.00
Gorilla, adult,34.50
Idiot,22.57

Mr. Davis, of England, having a collection of about eighteen hundred cranial specimens obtained from different quarters of the globe, ascertained the relative volume of brain in different races, by filling the skulls with dry sand. He found that the European averaged 92 cubic inches, the Oceanic 89, the Asiatic 88, the African 86, the Australian 81. Dr. Morton, of Philadelphia, had a collection of over one thousand skulls, and his conclusions were that the Caucasian brain is the largest, the Mongolian next in size, the Malay and American Indian smaller, and the Ethiopian smallest of all. The average weight of brain, in 278 Europeans, was 49.50 oz., in 24 White American soldiers, 52.06 oz., indicating a greater average for the American brain.

OUNCES
The brain of Cuvier, the celebrated naturalist, weighed64.33
Ruloff, the murderer and linguist,59.00
Dr. Spurzheim—phrenologist,55.06
Celebrated philologist,47.90
Celebrated mineralogist,43.24
Upholsterer,40.91

The weight of the human brain varies from 40 to 70 oz.; that of idiots from 12 to 36 40 oz. The average of 273 male European brains was 49½ oz., while that of 191 females was 44 oz. If we compare the weight of the female brain with that of the body, the ratio is found to be as 1:36.46, while that of the male is as 1:36.50; showing that, relatively, the female brain is the larger. It appears that neither the absolute nor relative size of the cerebrum, but the amount of gray matter which it contains, is the criterion of mental power. Although a large cerebrum is generally indicative of more gray matter than a small one, yet it is ascertained that the grey substance depends upon the number, and depth of the convolutions of the brain, and the deeper its fissures, the more abundant is this tissue. It is this substance which is the source of thought, while the white portion only transmits impressions.

We do not wish to underrate any attempt heretofore made to classify the functions of mind and assign to them an appropriate nomenclature. It is not unusual for scientists to give advice to phrenologists and point out the fallacies of their system; but it is hardly worth while to indulge in destructive criticism, unless something better is offered, as the day has passed for ridiculing endeavors to understand and interpret the physiology of the brain. The all important question is, not whether phrenologists have properly located and rightly earned all the faculties of mind, but have their expositions been useful in the development of truth. While endeavoring to connect each mental power with a local habitation in the brain, the system of phrenology may be chargeable with some incongruous classification of the faculties, and yet it has furnished an analysis of the mind which has been of incalculable service to writers upon mental philosophy. Phrenology, in popularizing its views, has interested thousands in their own organizations and powers, who would otherwise have remained indifferent. It has called attention to mental and bodily unities, has served as a guide to explain the physical and psychical characteristics of individuals, and has been instrumental in applying physiological and hygienic principles to the habits of life, thus rendering a service for which the world is greatly indebted. Samuel George Morton, M.D., whose eminent abilities and scholarship are unquestionable, employs the following language:

"The importance of the brain as the seat of the faculties of the mind, is pre-eminent in the animal economy. Hence, the avidity with which its structure and functions have been studied in our time; for, although much remains to be explained, much has certainly been accomplished. We have reason to believe, not only that the brain is the center of the whole series of mental manifestations, but that its several parts are so many organs, each one of which performs its peculiar and distinctive office. But the number, locality, and functions of these several organs are far from being determined; nor should this uncertainty surprise us, when we reflect on the slow and devious process by which mankind has arrived at some of the simplest physiological truths, and the difficulties that environ all inquiries into the nature of the organic functions."

We may here allude to the recent experimental researches with reference to the functions of various portions of the brain, prosecuted by Dr. Ferrier, of England. He applied the electric current to different parts of the cortical substance of the cerebrum in lower animals which had been rendered insensible by chloroform, and by it could call forth muscular actions expressive of ideas and emotions. Thus, in a cat, the application of the electrodes at point 2, Fig. 77, caused elevation of the shoulder and adduction of the limb, exactly as when a cat strikes a ball with its paw; at point 4, corrugation of the left eye-brow, and the drawing inward and downward of the left ear; when applied at point 5, the animal exhibited signs of pain, screamed, and kicked with both hind legs, especially the left, at the same time turned its head around and looked behind in an astonished manner; at point 6, clutching movement of the left paw, with protrusion of the claws; at point 13, twitching backward of the left ear, and rotation of the head to the left and slightly upward, as if the animal were listening; at point 17, restlessness, opening of the mouth, and long-continued cries as if of rage or pain; at a point on the under side of the hemisphere, not shown in this figure, the animal started up, threw back its head, opened its eyes widely, lashed its tail, panted, screamed and spit as if in furious rage; and at point 20, sudden contraction of the muscles of the front of the chest and neck, and of the depressors (muscles) of the lower jaw, with panting movements. The movements of the paws were drawn inward by stimulating the region between points 1, 2, and 6; those of the eyelids and face were excited between 7 and 8; the side movements of the head and ear in the region between points 9 and 14; and the movements of the mouth, tongue and jaws, with certain associated movements of the neck, being localized in the convolutions bordering on the fissure of Sylvius (B), which marks the division between the anterior and middle lobes of the cerebrum. Dr. Ferrier made similar experiments on dogs, rabbits, and monkeys. The series of experiments made on the brain of the monkey is said to be the most remarkable and interesting, not only because of the variety of movements and distinctly expressive character of this animal, but on account of the close conformity which the simple arrangement of the convolutions of its brain bears to their more complex disposition in the human cerebrum. It is premature to say what import we shall attach to these experiments, but they have established the correctness of the doctrine, advanced on [page 105], that thought, the product of cerebral functions, is a class of reflex actions. The cerebrum is not only the source of ideas but also of those co-ordinate movements which correspond to and accompany these ideas. Certain cerebral changes call forth mental states and muscular movements which are mutually responsive. They indicate that various functions are automatic, or dependent upon the will, and, as we have seen, experiments indicate that the electric current, when applied to the cerebrum, excites involuntary reflex action. We cannot say how far these experimental results justify the phrenological classification of the faculties of mind, by establishing a causative relation between the physical and psychical states. This short and unsatisfactory account furnishes one fact which seems to support the claim of such a relation: the apparent similarity between the motor center of the lips and tongue in lower animals, and that portion of the human cerebrum in which disease is so often found to be associated with Aphasia, or loss of voice. While these experiments are by no means conclusive in establishing a theory, yet they favor it.

It is wonderful that nervous matter can be so arranged as not only to connect the various organs of the body, but at the same time to be the agent of sensation, thought, and emotion. It is amazing, that a ray of light, after traversing a distance of 91,000,000 miles, can, by falling upon the retina, and acting as a stimulus, not only produce a contraction of the pupil, but excite thoughts which analyze that ray, instantly spanning the infinitude of trackless space! The same penetrative faculties, with equal facility, can quickly and surely discern the morbid symptoms of body and mind, become familiar with the indications of disease, and classify them scientifically among the phenomena of nature. The symptoms of disease which follow certain conditions as regularly as do the signs of development, and mind itself is no exception to this uniformity of nature. Thoughts result from conditions, and manifest them as evidently as the falling of rain illustrates the effect of gravity. The perceptive and highest emotive faculties of man depend upon this simple, but marvelously endowed nervous substance, which blends the higher spiritual with the lower physical functions. The functions of the body are performed by separate organs, distinguished by peculiar characteristics. To elucidate the distinctions between dissimilar, mental faculties, we have assigned their functions, with characteristic names, to different regions of the head. As they unquestionably influence the bodily organs, we are sustained by physical analogy, in our classification. Our knowledge of the structure and functions of the nervous system is yet elementary, and we are patiently waiting for scientists to develop its facts, and verify them by experimental investigations and such researches as time alone can bring to perfection. While real progress moves with slow and measured foot-steps, the inspirations of consciousness and the inferences of logic prepare the popular mind for cerebral analysis. No true system can contradict the facts of our inner experience; it can only furnish a more complete explanation of their relation to the bodily organs. It should be expected that such careful and pains-taking experiments, as are necessary to establish a science, will be preceded by intuitive judgments and accredited observations, which may be, for a time, the substitutes of those more abstruse in detail.

We have, in accordance with popular usage, treated the organs of thought as having anatomical relations. The views which we have presented in this chapter may seem speculative, but the facts suggesting the theory demand attention, and we have attempted to gather a few of the scattered fragments and arrange them in some order, rather than leave them to uncertainty and greater mystery. It is by method and classification that we are enabled to apply our knowledge to practical purposes. Possibly, to some, especially the non-professional, an allusion to the fact that cerebral physiology contributes to successful results in the practice of medicine, may seem to be an exaggerated pretension. None, however, who are conversant with the facts connected with the author's experience, will so regard this practical reference, for the statement might be greatly amplified without exceeding the bounds of truth. Physicians generally undervalue the nervous functions, and overlook the importance of the brain as an indicator of the conditions of the physical system, because they are not sufficiently familiar with its influence over the bodily functions. Pathological conditions are faithfully represented by the thoughts, and words, when used to describe symptoms, become the symbols of feelings which arise from disease. How few physicians there are who can interpret the thoughts, and glean, from the expressions and sentences of a letter, a correct idea of the morbid conditions which the writer wishes to portray! Each malady, as well as every temperament, has its characteristics, and both require careful and critical analysis before subjecting the patient to the influence of remedial agents.

In a treatise by Dr. J.R. Buchanan, entitled "Outlines of Lectures on the Neurological System of Anthropology," are presented original ideas pre-eminently useful to the physician. His researches, and those of later writers, together with our own investigations, have greatly increased our professional knowledge. It is by such studies and investigations that we have been prepared to interpret, with greater facility, the indications of disease, and diagnose accurately from symptoms, which have acquired a deeper significance by the light of cerebral physiology. We are enabled to adapt remedies to constitutions and their varying conditions, with a fidelity and scientific precision which has rendered our success in treatment widely known and generally acknowledged. We annually treat thousands of invalids whom we have never beheld, and relieve them of their ailments. This has been accomplished chiefly through correspondence. When patients have failed to delineate their symptoms currently, or have given an obscure account of their ailments, we have been materially assisted in ascertaining the character of the disease by photographs of the subjects. The cerebral conformation indicates the predisposition of the patient, and enables us to estimate the strength of his recuperative energies. Thus we have a valuable guide in the selection of remedies particularly suited to different constitutions. In the treatment of chronic diseases, the success attending our efforts has been widely appreciated, not only in this, but in other countries where civilization, refinement, luxurious habits, and effeminating customs, prevail. This fact is mentioned, not only as an illustration of the personal benefits actually derived from a thorough knowledge of the nervous system, but to show how generally and extensively these advantages have been shared by others.

A careful study of cerebral physiology leads us deeper into the mysteries of the human constitution, and to the philosophical contemplation of the relations of mind and body. Self-culture implies not only a knowledge of the powers of the mind, but also how to direct and use them for its own improvement, and he who has the key to self-knowledge, can unlock the mysteries of human nature and be eminently serviceable to the worlds For centuries the mind has been spreading out its treasury of revelations, to be turned to practical account, in ascertaining the constitution, and determining better methods of treating disease. Since comparative anatomists and physiologists have revealed the structure of animals and the functions of their organs, from the lowest protozoan to the highest vertebrate, the physician may avail himself of this knowledge, and thus gain a deeper insight into the structure and physiology of man. An intimate acquaintance with the physical, is a necessary preparation for the study of the psychical life, for it leads to the understanding of their mutual relations and reactions, both in health and disease.

Consciousness, or the knowledge of sensations and mental operations, has been variously defined. It is employed as a collective term to express all the psychical states, and is the power by which the soul knows its own existence. It is the immediate knowledge of any object whatever, and seems to comprise, in its broadest signification, both matter and mind, for all objects are inseparable from the cognizance of them. Hence, the significance of the terms, subjective-consciousness and objective-consciousness. People are better satisfied with their knowledge of matter than with their conceptions of the nature of mind.