what he intended to say, but that, just as he was about to pronounce the word, it went entirely out of his memory. After two days the pain returned, and words again were lost. He laboured under hepatic disease, and also disease of the heart. He died about a week after the first attack upon the organ of Language, suffering most part of that time great pain in both anterior lobes of the brain. A post-mortem examination could not be obtained.

21st March 1836.

ARTICLE XII.

1. THE PHYSIOLOGY OF DIGESTION, considered with Relation to the Principles of Dietetics. By ANDREW COMBE, M. D., Fellow of the Royal College of Physicians of Edinburgh, and Physician in Ordinary to their Majesties the King and Queen of the Belgians. Maclachlan and Stewart, Edinburgh; and Simpkin, Marshall, and Co., London. 1836. Post 8vo. Pp. 332.

2. DISCOURSE ON THE IMPORTANCE OF THE STUDY OF PHYSIOLOGY AS A BRANCH OF POPULAR EDUCATION; Delivered at Edinburgh, on 5th March 1836, as Introductory to a Short Series of Lectures on that Subject. By JOHN FLETCHER, M. D., F. R. C. S. E., Lecturer on Physiology, and on Medical Jurisprudence, in the Argyle Square School of Medicine. Edinburgh: A. and C. Black; J. Anderson, jun. ; and Carfrae and Son. 1836, 12mo. Pp. 24. 3. THE MORAL REFORMER, AND TEACHER ON THE HUMAN CONSTITUTION. Edited by Wм. A. ALCOTT. Nos. I. to IX. Boston, U. S., Light and Horton. January to September 1835. 12mo. 4. REMARKS ON THE INFLUENCE OF MENTAL CULTIVATION AND MENTAL EXCITEMENT UPON HEALTH. By AMARIAH BRIGHAM, M. D. With Notes by ROBERT MACNISH, Author of "The Anatomy of Drunkenness," &c. &c. John Reid and Co. Glasgow; Oliver and Boyd, Edinburgh; Whittaker and Co., London, 1836. 18mo. Pp. 137.

5. THE NECESSITY OF PHYSICAL CULTURE TO LITERARY MEN, AND ESPECIALLY TO CLERGYMEN. By EDWARD REYNOLDS, M. D., of Boston, U. S. Forming No. VI. of The Student's Cabinet Library of Useful Tracts. Edinburgh: Thomas Clark. 1835. 18mo. Pp. 34.

THE conviction is rapidly making progress among reflecting persons, that in no way is it possible to improve the human mind, and preserve it in vigour, except by ameliorating and strengthening the cerebral organization. But although the brain is the organic part through which exclusively the mental powers can be changed or affected, yet so closely is it linked with the

rest of the body, that without keeping the whole in good condition, its own vigour is necessarily impaired. Dr Combe, in the eighth and ninth chapters of his former volume, "The Princi ples of Physiology applied to the Preservation of Health, and to the Improvement of Physical and Mental Education," pointed out the laws of exercise which regulate the brain, considered as a separate organ; in his present work, and several chapters of the former, he shews the influence exerted upon it by the state of the digestive, respiratory, circulating, and excretory functions. The importance of these subjects in relation to the mind and brain is easily understood. Every part of the human body is incessantly undergoing waste of its substance, from the constant activity of the absorbent vessels and those of excretionthe latter being chiefly the skin, lungs, bowels, and kidneys. By this loss of substance the organ is weakened; its function languishes; and, unless repaired by a supply of fresh materials, it becomes altogether unfit for the performance of its duty. One of the offices of the blood is to renovate the body, by laying down in all parts of it the substances of which they respectively stand in need. To the bones it supplies bone, to the muscles flesh, and to the brain the materials of which that viscus is composed. That the body may be properly nourished, therefore, the blood must be sufficiently copious, and its quality must he healthy and rich. Now, it is obvious, that to realize these conditions two circumstances are indispensable: first, the materials of which the blood is composed must be good and abundant; and, secondly, the organs which convert them into blood must be capable of vigorously performing this operation. From materials of bad quality good blood cannot be made, and by weak or unhealthy organs even the best materials cannot be turned to proper account. Food and atmospheric air are the materials from which the blood is elaborated; and the organs by which the process is performed are the stomach, bowels, and lungs. Other parts, however, such as the teeth, liver, and pancreas, lend their assistance in this important work. Food taken into the mouth is, by the teeth and saliva, converted into a soft mass, and thus prepared for deglutition and subsequent changes. On arriving at the stomach it excites the secretion of the gastric juice, a fluid which has the power of reducing all kinds of aliment to a homogeneous pulpy substance, called chyme. In this condition the food passes into the bowels, where, by the admixture of bile from the liver, and pancreatic juice from the pancreas, it is converted into two distinct portions-a milky fluid called chyle, and a thick residuum, which, being of no use to the body, passes through the bowels and is discharged. From the intestines the chyle is sucked up by small vessels called the lacteals, which unite and form the thoracic duct, whose course

is upwards along the spinal column. On arriving at the top of the chest, this duct unites with the subclavian vein, just before it reaches the right side of the heart; and in this way the chyle is poured into the general current of the venous blood. But although thus mingled with the blood, the chyle is not yet entirely fitted for its duties. To complete its preparation, it must be exposed to the action of the atmospheric air during respiration. This is accordingly done by its passing through the lungs along with the dark venous blood, which, in consequence of the deterioration that it has sustained in nourishing and stimulating the body, stands in need of the same change. In the course of this process, both the chyle and the venous blood are converted into red, arterial, or nutritive blood, which is afterwards distributed by the heart, through the arteries, to every part of the system.

One other condition is necessary for putting the blood into a healthy state. It must be purified by the sufficient performance of the functions of excretion. And hence, for example, the necessity of regularly cleansing the skin.

But it is not by supplying nourishment only that arterial blood invigorates the body. Its presence excites every organ to action; and the more excellent its quality, and the greater the velocity of its circulation, the more intense is the stimulus which it affords.

The brain is not less dependent on the blood for stimulus and support than the rest of the animal machine; and, consequently, every circumstance influencing the blood affects also the brain and its functions. If the food is defective, or of bad quality; if the air which we breathe is impure; if the stomach or liver is in a weak or morbid condition, so that it cannot furnish the gastric juice or bile necessary for chylification; if the lacteals or their glands (the mesenteric) are diseased, and therefore unable to convey the chyle to the blood vessels; if, by neglecting ablution of the skin, we unfit it for exhaling the noxious particles of the blood; if the lungs are too small, or diseased; if the heart is weak and unable to circulate the blood with sufficient force; if, through neglect of muscular exercise, we permit the circulation, the breathing, and the functions of excretion to languish ;-in one and all of these cases, the vigour of the brain is, to a greater or less extent, impaired. But this is not all: for, in consequence of the intimate connexion between the brain and the digestive organs by means of the nerves, their diseases influence the brain sympathetically, and often give rise to serious derangement of mind. Thus, even without reference to the value of health for its own sake, it becomes of great importance, with a view to mental efficiency, that we should be aware of the qualities of food and air, the relations of these to the human

body, the rules by which we ought to be guided in selecting and apportioning our aliment, and the principles by attention to which the health of the blood-making organs may be secured.

But

Such is the information which Dr Combe affords in his work on Digestion, and in the other volume above referred to. His present treatise is divided into two parts-" The Physiology of Digestion," and "The Principles of Dietetics viewed in relation to the Laws of Digestion." In the first chapter of the former division, he shews that food is necessary to supply waste, both in vegetables and in animals. Vegetables draw nourishment, by means of their roots, from the soil; but animals, being locomotive, need a receptacle into which the food may be conveyed, and whence the lacteals (which are analogous to the vessels of the roots of plants) may at leisure suck up the necessary aliment. Such a receptacle are the stomach and bowels. something else is still required. The animal must have an inducement to fill the receptacle, and be enabled, moreover, to proportion the supply to the necessities of the body-varying, as these do, with the rapidity of its waste and growth. For this twofold purpose, the appetites of hunger and thirst are given; and Nature has so arranged, that, in the healthy system, their craving arises only when food is necessary, and ceases when enough has been taken in. Dr Combe accordingly proceeds, in Chapter II, to treat of hunger and thirst, which he shews to be affections of the brain, excited by certain conditions of the stomach and body at large. The third chapter is on the functions of mastication, insalivation, and deglutition, and the organs by which they are performed. The author then proceeds, in Chapter IV, to consider the stomach and gastric juice, and gives a most interesting account of the observations made by an American physician Dr Beaumont, on the stomach of a Canadian named Alexis St Martin. This man was wounded, in 1822, by the accidental discharge of a musket, which made an opening through the integuments and ribs into the stomach. The wound healed, but the aperture remained, being closed up only by a valve opening inwards. Dr Beaumont made a long course of observations on the phenomena of digestion, the results of which are of singular interest and importance, but to which we cannot do more than allude. Dr Combe's fifth chapter is on the Theory and Laws of Digestion; and the next on Chylification and the organs concerned in it-concludes the first part of the work. Part Second is subdivided as follows: Chap. I. Times of Eating;-II. On the proper quantity of Food;-III. On the kinds of Food ;-IV. Conditions to be observed before and after Eating;-V. On Drinks;-VI. On the proper regulation of the Bowels. This portion of the volume is replete with valuable instruction, and is eminently practical in its expositions. Of these,

however, neither our limits nor the objects of this Journal admit of a detailed analysis. We shall merely quote, as a specimen, some of the author's observations on the mutual influence of the brain and stomach, this being a subject more particularly within our province.

"Among the circumstances which favour digestion," says he, "the observance of bodily rest and mental tranquillity for some time before and after every meal, is perhaps the most important; its influence depends on a well known law of the animal economy, already frequently alluded to, but to which, that it may be fully understood, I must again shortly refer.

"Whenever any living part is called into vivid action, an increased flow of blood and of nervous energy towards it immediately commences, to enable it to sustain the requisite degree of excitement, and continues till some time after the activity has ceased. In accordance with this law, whenever food is swallowed, the lining membrane of the stomach becomes suffused with blood, and, owing to the greater distention of its vessels, its colour changes from a pale pink to a deep red hue. After digestion is completed, and the unusual supply of blood is no longer required, the vessels again diminish, and the colour returns to its original tint. It St Martin's stomach, these changes were so often seen by Dr Beaumont, as to render their occurrence as fully demonstrated as any circumstance with which we are acquainted."

"It is obvious, however, that the great afflux of blood which takes place towards the stomach and intestines during digestion, cannot occur without a corresponding diminution in the quantity circulating on the surface and in other distant parts of the body, attended of course with a diminished power of action in them. Hence, for some time after a full meal, there is an inaptitude for vigorous thinking and bodily exertion, a depression of respira tion, and, in delicate persons, a degree of coldness or chill felt over the whole body. But, under ordinary circumstances, this depression is not of long continuance. After the requisite secretions have been provided for the solution of the food and the formation of the chyle, a reaction and change in the distribution of the blood, now partially renewed by the admixture of nutritive chyle, ensue, and, by the stimulus which they afford, soon fit the person for the active resumption of his ordinary duties.

"That this impaired activity of the other functions after a full meal is natural, and intentionally arranged by the Creator, is plain, both from its universality among all kinds of animals, and from the mode in which it is produced. Among the lower creatures, the sluggishness induced by eating increases in proportion to the degree in which they gorge themselves with food. The boa constrictor, after a plentiful repast, slumbers for a