good not less in the Living body than in the Inorganic world, I was myself among the carliest to maintain. That in the most powerful muscular effort which can be called forth by the Human Will, there is no more a creation of Energy than in an Automatic convulsion, I believe as firmly as Professor Clifford. And that the general tendency of modern scientific research is to extend the domain of Law to every form of mundane change the belief in the Uniformity of Causation being now assumed as axiomatic in all scientific procedure-I recognise as fully as Mr. Herbert Spencer.-Preface, p. xvi.

thought either of any law by which this succession is regulated, or of any power in himself of modifying them. We will, however, proceed a step further. Let us suppose these sensations divided into several similar groups. The observation of this regular recurrence constitutes an elementary knowledge for the Ego. He apprehends an order by which his sensations follow one another. Now, let us suppose that these groups, though infinite so far as appears in number, are divided into several classes (which we will denote by the letters of the alphabet), so that there are several A's, several B's, several C's, and so on; and, further, that an A is always succeeded by B, sometimes but not always, also by C, and never by D. The Ego now increases bis stock of knowledge, but it is still a communicated, not an acquired knowledge-it is the knowledge of an observer pure and simple, not of a thinker; it is the knowledge of Flamsteed, while noting and tabu

There is no question that automatism, including in that term both mental and bodily activities, plays a very large part in the life of every one. What the limits of that part are is the real question at issue, and this it is the object of Dr. Carpenter's work to point out. The book is, in fact, a survey of the borderland between the region of Physical Causation and Moral Causation, taking its departure from the ground of the physiologist. It naturally enters largely into anato-lating the lunar movements, not the knowmical details, which however necessary for the establishment of the author's argument in the minds of his fellow-experts, are the reverse of attractive to the general reader. We will therefore endeavour to spare him as much of these as we can without injury to the understanding of the case.

That all our knowledge of the external world arises from the impressions made upon our senses is allowed by all philosophers of whatever school since the time of Locke; but the really important point to ascertain is, whether, in the very act of acquiring this knowledge, we have not evidence of something more than the external world--that is, of the Ego, the sentient, subject, our own personality. It might be possible to acquiesce in a denial of this, if the whole of our existence consisted of one unvarying, single sensation; but as soon as ever any the least variation of this is perceived, personality shows itself in its simplest form, viz.-as the identical subject of two diverse sensations. Let us merely suppose these sensations multiplied and varied, each in its turn leaving its trace in the shape of a remembrance, and the result will be something analogous to what is continually experienced in a dream, where image after image springs up in an apparently arbitrary manner, the sleeper bearing no other part in it than that of the spectator of a moving phantasmago

ria.

Now in this simplest form of personality there is not involved the idea either of knowing or of acting. The Ego is in it nothing more than the passive recipient of a string of impressions. He can have no

ledge of Newton, deducing from those movements, the law of gravitation. The Ego, by acquiring this knowledge, has become an ens sciens, but as yet is in no respect an ens agens. And however much we may suppose the groups of sensations varied and complicated, and in consequence the aggregate of the communicated knowledge increased for the Ego, he remains still altogether passive, the product (except so far as consciousness is concerned) of external forces, as much as the mature plant is the product of the pains bestowed upon it by the gardener. If then the matured powers of the man are really developed out of simple sensations by a similar process, however wonderful and elaborate, it cannot be contested that he must be classed in the same category as the plant.

The

But now let us see how far the phenomena even of infancy warrant any such conclusion. Our classes of sensations, just now denoted by the letters of the alphabet, are here those which reach the sentient subject, the infant, through his several senses. physiologist teaches us that in sight, for instance, a certain impression is made on the retina of the eye, just as in photography an impression is made on prepared glass; and the first effect of this is to generate nerveforce in the optic nerve along which it is transmitted to the ganglionic centre of the latter, which forms part of the sensorium.*

By this term may be understood the aggregate of the ganglia in which the spine and higher hemispherical portion of the brain, the the several nerves centre, lying under the

cerebrum.

The olfactory and the auditory nerves per- | elementary form implies attention, that is, form a precisely similar function in the case concentration upon some portion of whatof smelling or hearing. All these nerves ever is presented to the Ego to the comparhave in themselves no sensation; their sole ative neglect of the rest. Indeed, it seems employment being to convey, like a tele- undeniable, that even in any single experigraph, the message from without, and they ence of muscular resistance, there must be may be pricked or pinched without evoking awakened the consciousness of a force to any sign of pain. It is altogether different the exercise of which that resistance is with the nerves which minister to the power offered; in which case the evidence of the of movement, as well as convey to the Ego existence of the Ego as an active force, canthe information supplied by the senses of not but be regarded as arising contempotouch and of muscular resistance, and which, raneously with that of the existence of the on this account, have received the name of non-Ego-the external world, the limit of the sensori-motor nerves. Microscopic ob- such active force. servation exhibits them as bundles of minute fibres, of which each is isolated from the rest, like the wires in a submarine cable, by a peculiar substance known as the white substance of Schwann.' They are of two distinct kinds—the afferent, which convey to their proper ganglionic centres the sensations indicated by the touch, and the sense of muscular resistance, and the efferent, which, proceeding from these ganglionic centres, produce movement in the appropriate members through muscular contraction. The combination of the two is like a compound telegraphic arrangement, by which information is transmitted from the point A to the point B, and orders derived from that information (not the information itself) forwarded at once to a third point C. In many cases this is purely an automatic proceeding, as, for instance, when the soles of the feet are tickled, the involuntary result is a twitching convulsion of those members. But in others the volitional character is manifest, as when we find by our sensations that a weight carried on the shoulder is awkwardly placed, and therefore we vary its position to render it more tolerable.

Automatism, however, undoubtedly plays a very large part in the bodily actions, and, according to Dr. Carpenter, in mental operations also. The acts of breathing, of coughing, and of sneezing are mainly independent of the will. The muscular movements which effect them are evoked by agencies over which the will has no control. The beating of the heart is even more striking. It may be, and often is, modified by emotion, but never by a simple effort of will without the presence of emotion. It is obvious that but for this automatism, in many cases, there would be no security for the maintenance of life. The circulation of the blood would cease from mere neglect of the agency which keeps it in mction. But this Primary Automatism, as it may be called, yields in interest for the present purpose to Secondary Automatism, a name given (first by Hartley) to actions which come to be performed by habit without will, or even consciousness; but which were originally learned by volitional effort. Walking is the most obvious example of this class of actions. The power is attained gradually, and at the cost of considerable pains. The mere balancing of the Now, the first manifestation of volitional body in a standing position involves the movement in the infant is undoubtedly combined action of almost every muscle; obscure. He turns in his cradle towards a and the advance of the most finished acrobat light; and this is doubtless an automatic beyond this achievement is far less than result occasioned by the attraction of its that which he must have made in acquiring brightness. But the same can hardly be it. Yet it is a matter of daily experience said of his handling an object presented to that in walking we pay no attention whathim, which, if in its origin stimulated by ever to what we are doing after once dean external impulse, almost instantly assumes termining in what direction we shall proanother character, when he places the object ceed. Very generally we are altogether at different distances from his eyes, carries absorbed in conversation with a companion, it to his mouth, turns it in various ways, or, perhaps, in meditation on some subject strikes it against the side of his cradle, and which happens to occupy our minds. Mr. endeavours to pull it to pieces. It is im- Mill thought out the greater part of his possible for any one who watches these actsSystem of Logic' during his daily walks to conceive them to be nothing else than a sequence of phenomena, each springing out of the one preceding it by a mechanical necessity. There is manifestly a comparison going on of the different sensations that have been excited; and comparison in its most

between Kensington and the India House; and no one who passes through the Bank of Engiand, during business hours, will be able to fancy that, of the hurrying crowd he sees, a single individual is bestowing a thought upon that co-ordination of his muscular

actions,' without which it would, nevertheless, I spinal cord be divided in the middle, so that

be impossible for him to carry his dividendwarrant to his banker's.

But let us suppose one of these men of business suddenly seized with blindness. He would instantly stop in his career, although just before, while hastening over familiar ground, and taking no heed of anything but the matter uppermost in his thoughts, he was utterly unconscious that his eyes were rendering him any service at all. Here, then, it is plain that not only was there a mechanical co-ordination of the locomotive muscles, but likewise co-ordination

the forelegs remain connected with the upper part, and the hind legs with the lower, each pair of members may be excited to movement by a will not exhibit any consentaneous motions, stimulus applied to itself, but the two pairs as they will do when the spinal cord is undivided.'

เ

step, although the patient was quite unconble that in these cases, as recovery (which took place very slowly) progressed, and voluntary power gradually returned, the susceptibility to the involuntary reflex move

scious of the cause of them. It is remarka

In a case of paralysis of the lower extremities, recorded by Hunter, the patient was asked whether he felt the irritation by which 'reflex movements' in his legs were produced, and replied, No, sir, but you see my legs do.' In two cases of injury to the between them and the visual organs. Yet which sensibility of the legs was for a time spine, recorded by Dr. William Budd, in of this the merchant had not the slightest nearly destroyed, and voluntary action enconception. From the time he set out, tirely so, violent contractions followed the therefore, he has been the subject of an ex-tickling of a feather in the hollow of the intremely complicated automatism, no volition having been exerted by him any more than after having put himself into a cab, volition would have been exerted by him in driving it. The whole act of going from place to place is, of course, volitional; but the volitional character of it does not permeate the entire sequence of motions, but is derived Dr. Carpenter holds that the will, when from the initial purpose. The merchant wills to go to his banker's, and he wills to intellect, does not act directly upon the I carrying into action a determination of the go by walking. His purpose brings his eyes muscles which execute the mandate, but inand limbs into action, and between them directly through the automatic mechanism, they perform the operation which he desires of which the act of walking, as we have just to see effected; but they, nevertheless, per-seen, furnishes a familiar example. The form it automatically, his will no further in-head-quarters (so to speak) of this mechanterfering after having once given its comism is the axial cord, receiving, as it does, mand, and his attention being occupied by all the nerves of sense and giving out all the altogether different matters. nerves of motion; and this, under different modifications, is found in all animals.

The important part played by the cooperation of the senses, of which we are all the time unconscious, is exhibited most clearly in some cases of accident. Thus the sensory nerve of a limb may be paralysed, while the force of the motor nerves of the same limb remains. But the latter cannot by any effort of the will be brought into action (the sense of muscular resistance being lost through the paralysis of the sensory nerve) without the aid of the eye. A woman thus affected found that she could not support her infant on her arm without constantly looking at it. The removal of her eyes for a moment, in spite of her knowledge that the child was resting on her arm, and of her desire to sustain it, was at once followed by a relaxation of the contracted muscles.

ments diminished.

'We should form,' says Dr. Carpenter, ‘a very erroneous notion of what essentially constitutes the brain of a Vertebrated animal, and of the mutual relations of the aggregate of ganglionic centres of which it is composed, if we were only to study it in Man. For the great relative size and complexity of his Cerebrum tends to conceal the fundamental importance of those ganglionic centres on which it is superposed, and which constitute no less an important part of his brain than they do of that of Fishes; although their proportional size is so much less as to lead to their being commonly regarded as merely subordinate appendages to the Cerebrum. The brain of a FISH is almost entirely composed of an aggregate of ganglia of Sense, which may be regarded as collectively constituting its Sensorium, that is, according to ordinary phraseology, the "seat of consciousness," but, more correctly, the Nerve-centre, through the instrumentality of which the Ego becomes conconscious of Sense-impressions. Putting aside the rudimentary Cerebrum, therefore, we may regard the Axial Cord of the Fish (consisting of its Spinal Cord with the Sensory gan'If the head of a frog be cut off, and the glia) as the instrument, like the gangliated

The reflex movements, as those are called which are produced by the motor (or efferent) nerves in response to the messages veyed through the afferent nerves, are not necessarily accompanied by feeling.

cord of the insect, of its automatic move- the Sensori-motor tract on which the Cerements; of which such as are executed through the Spinal centres do not involve Sensation, whilst in those of which the Sensory Ganglia are the instruments, Sensation necessarily participates. When, on the other hand, in ascending the Vertebrate Series from Fishes toward Man, we compare the different grades of development of the Cerebrum with the successively augmenting manifestations of intelligence (as exhibited in what we must regard as an intentional adaptation of means to ends under the direction of experience), we find so remarkable a correspondence as scarcely to leave room for doubt that the Cerebrum is the instrument of those Psychical operations which we rank under the general designation, rational. In proportion as the actions of an animal are directed by this endowment, the number of them that can be said to be primarily automatic becomes not only relatively but absolutely limited; although many actions (especially in Man) which were in the first instance initiated by the Will, come after long habit to be as truly automatic as if they had been so originally.'

-P. 64.

After tracing the increasing relative magnitude of the cerebrum (or its analogue), as we ascend the scale of vertebrates from its lowest member, the fish, to its highest, man, Dr. Carpenter proceeds to that portion of his work which will chiefly interest the bulk of his readers-the inquiry into the mode in which this highest organ, the cerebrum, is subservient to those higher mental operations, the capacity for which specially characterises man, though among some of the other mammalia may be found (he thinks) distinct approximations to it. The general fact, that the development of the cerebrum indicates the predominance of intelligence over instinct, is universally allowed; and the principle seems to hold good to a great extent, not only when we compare different races of mankind, but even different individuals of the same race.

The anatomical distinction between the cerebral hemispheres of man and the analogous organ of other animals shows itself especially in the complexity of the arrangement of the nerve fibres of which the medullary substance is composed.

These may be grouped under three principal divisions. The first, which may be distinguished as the radiating fibres, connect the different parts of the Cortical layer* with

This Cortical layer' consists of nervecells spread out on the surface of the cerebrum; not as is the case with ordinary ganglia, of which latter they form a sort of internal nucleus. It is covered by the membrane called the pia mater, which, being entirely composed of blood-vessels held together by a connecting tissue, causes a far larger supply of

brum is superposed; and it is probable that there are two sets of these, one ascending from the terminals* of the sensory tract of the Axial Cord to the Cortical layer, and conveying to it the result of the physical changes produced in them by the Sense-impressions which they receive; the other descending from the Cortical layer to the terminals † of the motor tract of the Axial Cord, and conveying to them the Physical results of the changes which take place in itself. These fibres, which bring the instrument of Intelligence and Will into relation with that portion of the nervous apparatus which furnishes the Mechanism of sensation and of the automatic or instinctive motions, were called by a sagacious old Anatomist, Reil, the nerves of the internal senses. The second set of fibres brings the several parts of the Cortical layer into mutual communication. The arrangement of these commissural fibres is peculiarly complex in Man. The third set of fibres, termed intercerebral, connects the two hemispheres of the Cerebrum together by a broad band. This also is much more developed in Man than in any of the lower Mammalia. Birds. There is a rudiment of it only in Maris altogether wanting in Fishes, Reptiles, and supials and Rodials. Cases have occurred in which it has been nearly, or even entirely, deficient in Man; and it is significant that the chief defect in the characters of such individuals has been observed to be a want of forethought, i.e., of power to apply the experience of the past to the anticipation of the

future.'-P. 99.

It

There is no indication, in the case of man, of a transfer to the cerebrum of the proper attributes of the other nervous apparatus. Its substance is insensible, and no physical impression made upon it is felt by the subject of it. It has been removed from pigeons, the sensory ganglia being left intact; and the respondent motions to external impressions have remained unaltered. The bird seeks out the light parts of a partially illuminated room, and avoids objects that lie in its way. If thrown into the air it flies, and when sleeping at night, with closed eyes and its head under its wing, is roused by the slightest noise, just as in its normal condition.

There is, however, according to Dr. Carpenter, one characteristic of the cerebrum which is common to it and to the sensorimotor nerves-it is subject to reflex automatic action. Regarding memory, from his point of view, as the psychological expression of physical changes in the cerebrum,' he considers traces' (so to speak) to be left

blood to the cortical layer in proportion to its
substance than to any other part of the body.
The Thalami Optici.'

The Corpora Striata.'
The Corpus Callosum.'

which we are very familiar, we act just as automatically as in the case of walking, which has been considered above. We think in the language, and words spring up spontaneously, expressing the current of ideas which pass through our minds. But the acquisition of the language, even if it be our mother-tongue, is really the result of a long series of mental acts, each of which, on physiological principles, is recorded by some change in the condition of the brain, or of some portion thereof. The

in the latter by each idea which has been formed, and each emotion which has been experienced. These, however, rapidly fade away, and remain in the region of unconsciousness until recalled through the process of association. Thus the aggregate of our previous lives, rational and emotional, may be conceived of as a series of pictures on sensitive paper, soon becoming invisible, but still remaining potentially, and at once reproduced under favourable conditions. As an example of this, Dr. Abercrombie relates that a lady in the last stage of a chronic ill-structure of this portion is kept up according ness, at a lodging in the country, had her infant child brought to see her. After the child had grown up, without any recollection of her mother, she was taken, without knowing it to be such, into the room in which her mother had long before died. She exhibited at once marks of emotion, and explained them to her friends as occasioned by a distinct impression that she had been in the room before, and that a lady in bed there, who seemed very ill, had hung over her in tears. A very familiar instance of this reviviscence of dormant emotions, is the sense of anger or of shame which men feel when accidental circumstances recal to them some passage in their former lives in which they were grossly insulted, or in which they failed from weakness in any recognised duty; although, perhaps, for many years they may never have had the matter enter their minds.

The loss of recollection which generally follows upon stunning is a well-known phenomenon; but there are not wanting instances of an abnormal recollection being evoked by extraordinary circumstances. Dr. Abercrombie relates the case of a man brought into St. Thomas's Hospital, in a state of stupor from an injury of the head. When partially recovered, he spoke Welsh, a language which, before the accident, he had entirely forgotten from long desuetude; but when he had quite recovered, he again completely forgot his Welsh, and got back his knowledge of English. Another case is even more remarkable. A boy at the age of four suffered fracture of the skull, and was trepanned while in a state of complete stupor. After his recovery he retained no recollection either of the accident or the operation; but at the age of fifteen, during the delirium of a fever, he gave an account of the operation, and the persons who were present at it, with a correct description of their dress and other minute particulars.'

But the ordinary experience of life furnishes a good example of the way in which a temporary loss of recollection clearly exhibits itself. In speaking any language with

to the ordinary laws of nutrition; although the material particles continually change, just as the right arm of a blacksmith is maintained in a more highly-developed condition of the muscles; and facility in speaking the language is thus manifestly as completely a secondary automatic faculty as the skill of the accomplished musician, who (to use an illustration of Miss Cobbe's) will execute a piece of Bach's to perfection while carrying on a flirtation with the admirer who is turning over the leaves of her musicbook. Now everyone who has travelled has experienced the manner in which a foreign language, with which he has become tolerably familiar, so as habitually to think in it, rises to his lips with considerable difficulty after long desuetude, and yet comes back again to him after a week or ten days. If, again, his knowledge of the language is but small, and he endeavours to accelerate the rate of his advance by resolutely living only with the natives of the country, he will soon be surprised at his own progress; but if, while doing so, his habit of thinking in the language be interrupted by even a very short intercourse with his own countrymen, he will be equally surprised at the change for the worse which has been thereby produced. In this case, as in the two cases above-quoted, the physiologist would account for the phenomenon on the same principle. The portion of the brain which records the language has, for a time, been brought out of connection with that which ministers to the play of ordinary thought, and yet its mechanism is preserved in working order, ready to be called into action again under favourable conditions. In the last instance, the automatic mechanism of the mother-tongue comes into collision with that of the foreign language, the stronger with the weaker, and naturally disorders the latter, which can only be restored to its recent condition by isolation (a volitional act), and fresh efforts on the part of the learner.

The impairment of the memory in old age is one of the most obvious symptoms of the commencement of general decay.