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a close confinement to his room, in which an elevated and equable temperature is maintained, is attended with almost as many disadvantages as benefits to a patient labouring under phthisis; for the vitiation of the atmosphere, which necessarily takes place from the want of due ventilation, counterbalances, in a great measure, the good effects otherwise to be derived from this plan of treatment. Another, and very common plan, has been to send these patients to a milder climate during the seasons alluded to; this measure has proved eminently beneficial in some cases, but unhappily in a vast majority of instances, the unfortunate sufferer merely leaves his home, and the affectionate and ever-watchful attentions of his family and friends, to find an untimely grave on a distant shore. At the same time, however injudicious and cruel it may be to advise individuals whose lungs are ulcerated, or who present other symptoms of an advanced stage of phthisis, to seek for relief by a change of climate, there is not the shadow of a doubt, that in the earlier periods of this disease, and in those pulmonary affections which may lead to it, a removal to a more genial climate is beneficial.

In chapter second, Dr. Dunglison proceeds to the consideration of the important subject of food, or the materia alimentaria, respecting which more treatises have been written, and more absurd theories framed, than on any other topic connected with the science of medicine, contagion not excepted. We are, therefore, glad to meet with a plain, sensible, and practical series of observations like the present, which may be recommended to the perusal of general readers.

We shall not attempt to discuss whether man should live on vegetable or animal food alone; it is sufficient for us, that in the present state of society, and in this part of the world, that he is omnivorous, and the best argument in favour of this practice is, that it is perfectly consonant to health; the fact appears to be, that nature having fitted the human race to subsist indifferently on animal or vegetable food, or both, the circumstances of climate or locality under which nations or tribes have been placed, have in all cases led to the adoption of those articles of diet which were most readily attainable. In an advanced stage of civilization, and more especially in temperate climates, man derives his food. (under which we include condiments), from all the kingdoms of nature. Earth, air, and ocean, have been ransacked, and there is scarcely a living creature that has not at different times and in different nations been resorted to as an article of diet; and what is turned from with disgust by the inhabitants of one part of the world, is eagerly sought for as the greatest delicacy by the natives of another.

When speaking of the nutritive and digestible properties of food, the author observes that they are by no means synonymous and convertible terms.

Although one ounce of fat meat is estimated to afford nutriment equal to four ounces of lean, it requires far more labour on the part of the diges tive organs, and undergoes no change whatever in the stomach, whilst it remains much longer in that organ. This is a singular physiological fact. It has been generally conceived that the pylorus acts, as its name imports, the part of a janitor at the lower orifice of the stomach, and that it does not permit the food to pass into the small intestine, until it has undergone the physical process of chymification, that is, solution in the gastric secretions. Yet castor oil proceeds onwards with rapid progress, whilst a blander oil is detained longer than any other kind of aliment, and vege table substances pass on unchanged, or but little changed, as has been remarked in cases of artificial anus, much sooner than animal substances that are more easy of assimilation."

Broussais and others have attributed this to what they term an internal gastric sense, which exerts an elective agency, and detains the digestible, whilst it suffers the indigestible parts of the food to pass on. With all deference to this learned physiologist, we think that this admits of easy explanation, without the creation of an internal sense. When indigestible food is introduced into the stomach, it acts as an irritant, and as a natural consequence of the increased action thus induced, the offending substance is in most cases speedily expelled through the pylorus into the small intestines, where it may continue to exercise the same morbid influence, and thus cause purgation, by which it is finally ejected from the body.

The process of digestion being mainly one of solution, it must be evident that food should be presented to the stomach in a form that requires the least exertion of power on the part of that viscus. The author of "The Art of Invigorating and Prolonging Life,” justly, but quaintly observes

"Our food must be done either by our cook or by our stomach, before digestion can take place, and surely no man in his senses would willingly be so wanting in consideration to that organ as to give it the needless trouble of cooking it, and digesting it also, and thus waste its valuable, energies in work which a spit or stew-pan can do better."

The generality of alimentary articles become more digestible by the various culinary operations to which they are subjected; but this is not always the case: thus, oysters in a raw state appear to call on the digestive powers in a much less degree than when they are stewed, roasted, &c., and cabbage disagrees with more persons in a boiled than in a crude state.

We shall not attempt to follow Dr. Dunglison in his observations on each particular article of food, as we could not do justice to them without extending our remarks beyond all due limits; added to which, we are extremely sceptical as regards the criteria by which the digestibility or indigestibility of particular articles have been judged. In most cases the test has been, whether they suited the

state of the gastric organs of the writer. Now, idiosyncracy, habit, and the particular circumstances of the case, exercise so strong an influence, that it is almost impossible to decide, à priori, what will agree or disagree with an individual, and it is the height of absurdity to proscribe any article of diet because it has been found injurious in a few cases.

Perhaps," says our author, "the best opinion as regards the wholesomeness of an aliment, in the case of any particular individual, is comprised in the answer of the facetious Mandeville, who, when asked by the ladies of the court whether this or that article of diet was wholesome, demanded whether they liked it and it agreed with them; if so, it was wholesome."

To attempt to live by rule and measure with respect to our food, and to strive to establish a universal standard of the wholesomeness or unwholesomeness of the various articles composing it, would be as absurd as the practice of the philosophical tailors of Laputa, who, we are informed by Gulliver, though they manufactured clothes on abstract principles, never were so fortunate as to make them fit.

"It is impossible to indicate accurately the quantity of food proper for each individual. Children, and those in the age of adolescence, when every thing is undergoing development, require more nourishment than the adult or the aged. Yet the latter, especially when far advanced in life, appear to demand a larger quantity of food than the former. The assimilative organs in them perform their functions but imperfectly and tardily, and a much smaller proportion of nutritive matter is separated; hence it is that more of the raw material is necessary."

Though we agree with Dr. Dunglison in the first of these propositions, we are by no means disposed to admit that the aged should partake largely of food; for as the digestive function in them is also imperfect, an accumulation of the raw material, as the author terms it, cannot fail of being productive of gastric distress, and of calling into action those fatal disorders of the encephalon to which most individuals at an advanced period of life are peculiarly liable. A large proportion of the apoplexies and palsies of the old occur soon after the ingestion of a meal. The proper diet at this term of existence should be such as is at the same time nutritious and easy of digestion.

All writers agree that it is of importance that the number of meals, and the times at which they are taken, should be regular. By this means, as has been justly observed by Dr. Darwin, the stomach is not only stimulated to requisite action by the food ingested, but also by periodical habit. This latter undoubtedly exercises no little sway, for it is well known that if a meal be not taken at the usual time, the feeling of hunger which existed is very apt to cease, until the return of the next period at which food is habitually taken.

"The number of meals must in a great measure be regulated by the age. Children eat more frequently than adults, with impunity, and even with advantage, but it is important that they should not take too much at a time; and in this way digestion may be readily accomplished, as the quantity of food may not exceed the powers."

This is sound doctrine, but it should not be abused; much mischief has been done to invalids and dyspeptics by constantly keeping their gastric organs in a state of excitement by the undue repetition of the times of their taking food; and the common adage that "the stomach is like a schoolboy, always at mischief unless it be employed," is, like too many of its class, founded on error, and is the more dangerous, because it chimes in with the popular dread of debility.

We shall not stop to discuss the number of meals that should be taken in the day, as this must depend upon a variety of contingent circumstances, of, which habit is the most influential; those usual in this country have become so firmly established by custom and convenience as to preclude the necessity of saying anything on the subject. With regard to the evening repast, both theory and experience concur in demonstrating that it should be light, and composed in a great measure of fluids, as the stomach, having accomplished the heavier task imposed on it, that of digesting the mass of solid food taken in at dinner, requires the presence of bland and diluting fluids, to aid its restoration to a state of calm and quiescence.

As regards supper, there ought to be but one opinion; that it is seldom necessary, and in most cases positively injurious.

"When the stomach is loaded, the circulation is interfered with, and the brain receives irregular impressions, which give occasion to painful and distressing dreams, nightmare, and, when in a higher degree, to somnambulism. Hence it is in civic life, where plethora is apt to be induced by continued full living, apoplexy so frequently follows a surfeit at supper."

At the same time, a light repast before retiring to rest is allowable or even requisite to dyspeptics, and almost every practitioner must have met with cases where, if food was not taken at this time, patients passed a restless and uneasy night, from a nervous irritation in their gastric organs.

We must, however, hasten to conclude our observations and extracts from this part of Dr. Dunglison's work, although we are sensible we have given but a feeble idea of it, and have not, perhaps, done justice to him in giving so cursory a sketch of it. We are glad to find that he has not followed the example of most writers on dietetics, and enrolled himself under the banner of the antiphlogistists, who have done more harm by inducing their unfortunate patients to restrict themselves to the most simple and mawkish

articles of food, than would have occurred if they had remained "Epicuri de grege porci."

Dr. Dunglison next makes some very apt and judicious comments on a custom by far too prevalent in this country, the use of tobacco, which we are convinced has occasioned more derangements of the gastric organ than have ever arisen from excesses in eating and drinking.

"When tobacco is used," says he, “in any shape, to excess, it blunts the sensibility. not only of the organs with which it comes in contact, but of the whole nervous system; or it induces so great a susceptibility to impressions, that existence becomes painful.”

The only defence that has been made of the employment of this poisonous herb is, that it is useful in preventing the impression of miasmata; but, as is observed by Dr. Dunglison, there does not appear to be much foundation for the belief. In fact, a custom must be a very bad one, when its votaries are never solicitous to gain new adherents; and we can fully credit the declaration of Dr. Franklin, that he had never known a man who used tobacco, who advised him to follow his example.

The third chapter is devoted to the consideration of clothing, and contains some very judicious remarks on the importance of a strict attention to adapting it to meet the rapid vicissitudes of temperature. The great requisites of a dress are, to be so adapted to the body as not to obstruct the motion of the limbs or the more important functions of life, and to be formed of such materials as will preserve the skin at that degree of temperature that is most agreeable. It must be evident, that those articles which are bad conductors of caloric are the warmest when the external temperature is lower than that of the body, and, on the contrary, are the coolest when the atmospheric heat is greater than the usual temperature of

man.

Clothes, formed of hemp or linen, are good conductors of caloric, and therefore cool. They readily imbibe and part with humidity, and when wet they are better conductors of caloric than when dry. They are, therefore, not well adapted for cool climates and seasons. Cotton is a worse conductor of caloric, and absorbs and retains a portion of the perspiration. It is conseqnently a warmer clothing. Whilst wool is a very bad conductor of caloric, and never allows the matter of perspiration to escape to such an extent as to cause a powerful sensation of cold."

Hence the great advantage of wearing flannel next the skin in cold and temperate regions, as it forms one of the best protections against the impression of cold, and the sudden vicissitudes of temperature to which such countries are continually liable. But the properties of clothing do not depend on their texture only; their colour exercises no little influence. As white reflects the calorific