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connexions which are thus traceable by the anatomist, furnish a good deal of information to the physiologist in reference to the dependent and relative affections now referred to; but they do not, it must be admitted, explain the whole of the phenomena ; and if ever structure should furnish a satisfactory exposition of all the sympathies and peculiarities of the animate machine, our knowledge of it must be much more accurate than it is at present.
There is one particular connected with the digestive or assimilating process itself, which is still involved in considerable obscurity : we allude to the circumstance of liquids being conveyed from the stomach into the circulation, apparently by a different and less circuitous route than through that of the chyliferous vessels.
. It was long supposed,' says Dr. Paris, that liquids, like solids, passed through the pylorus into the small intestine, and were absorbed together with the chyle, or rejected with the excrement. It is not asserted that this never occurs; but it is evident beyond con tradiction, that there exists another passage by which liquids can be conveyed to the circulation ; for it has been proved, that if a ligature be applied round the pyloric orifice, in such a manner as to obstruct the passage into the duodenum, the disappearance of the liquid from the cavity of the stomach is not so much as retarded. It is evident, therefore, that there must exist some other passage, although its nature and direction remain a matter of conjecture.* I am strongly persuaded, that the vena porta (the large vein carrying blood to the liver) constitutes one of the avenues through which liquids enter the circulation; and in my Pharmacologia, I have expressed my belief, and supported it by various arguments, that through this channel, certain medicinal substances find their way into the blood. In order to discover whether drinks are absorbed along with the chyle, M. Majendie made a dog swallow a certain quantity of diluted alcohol during the igestion of his food; in half an hour afterwards, the chyle was extracted and examined; it exhibited no traces of spirit ; but the blood exhaled a strong odour of it, and by distillation yielded a sensible quantity.
* It has been proved by examinations after sudden death from intoxication, that part of the liquid ingesta has been transferred almost instantaneously even to the brain. Mr. Hare gives one or two remarkable instances of this ; and in Dr. Cooķe's Treatise on Apoplexy, a case well authenticated is recorded, of a fluid being found in the ventricles of the brain exactly similar to gin, upon the inspection of the body of an individual whose death had been immediately occasioned by that spirit taken in a very large quantity. We assume, in these cases, the circumstance of immediate transference, since it must be effected before the vital spark is extinct.
• When liquids are introduced into the stomach, the changes which they undergo are determined by the nature of their composition.
• When a liquid holding nutritive matter in solution, is introduced into the stomach, it is either coagulated by the gastric juice, or its watery part is absorbed, and the solid matter deposited in the stomach'; in both cases, the product is afterwards chymified in the manner already described. "Milk appears to be the only liquid aliment which nature has prepared for our nourishment; but it seems that she has at the same time provided an agent for rendering it solid; hence, we may conclude that this form is an indispensable condition of bodies which are destined to undergo the process of chymification and chylification ; and that unless some provision had existed for the removal of aqueous fluids from the stomach, the digestive functions could not have been properly performed. When the broth of meat is introduced into the stomach, the watery part is carried off, and the gelatine, albumen, and fat are then converted into chyme. Wine and fermented liquors undergo a similar change; the alcohol which they contain, coagulates a portion of the gastric juices, and this residue, together with the extractive matter, gum, resin, and other principles which the liquid may contain, are then digested. Under certain circumstances, these liquids may observe a different law of decomposition, which will perhaps in some measure explain the different effects which such potations will produce: for example, the spirit may undergo a partial change in the stomach, and be even digested with the solid matter, or, on some occasions, be converted into an acid by a fermentative process. This will be more likely to occur in resinous liquors, which contain ingredients favourable to the production of such a change ; and hence, the less permanent and mischieve ous effects of wine than of spirits. The liquid termed punch will, cateris paribus, produce a less intoxicating effect than an equivalent quantity of spirit and water ; this may be accounted for by supposing that a portion of the alcohol is digested by the stomach into an acid; a process which is determined and accelerated by the presence of a fermentable acid like that of lemon, aided perhaps by the saccharine matter.
• Oil, although possessed of the fluid form, does not appear to observe the laws which govern the disposal of these bodies; it is not absorbed, but it is entirely transformed into chyme in the stomach. To effect this, however, it seems essential that the stomach should be in a state of high energy, or it undergoes chemical decomposition and becomes rancid; nor will the stomach, unless it be educated to it, like those of some northern nations, digest any considerable quan, tity of it; and since it cannot be absorbed, it must find its exit through the alimentary canal, and consequently prove laxative.'
We have presented this long extract from the classical production of Dr. Paris, partly because it clearly and ably explains the fact to which we have above adverted, in reference to the different circumstances under which liquid and solid ingesta eventually become integral portions of the circulating
mass; and partly, because we shall have occasion by and by to refer to the question recently so much agitated, viz. whether, and to what extent, Iquids ought to be taken in combination with solid aliment. Dr. Paris, in the passage above cited, uses this expression ; ' the stomach inust be in a state of
high energy. Now it becomes important to inquire, what is precisely signified by the term, high energy. We have al. ready shewn, by the anatomical outline that has been traced, how dependent the ventricular function must be upon the nervous power. It is indeed so dependent upon it, that every part and portion of the chylopoietic and assistant chylopoietic organization, every blood vessel and every secreting surface, may be ready to commence, and prepared to proceed in their several departments, yet waiting the mandates of the nervous impulse. Should that impulse be either defective or irregular, every thing is thrown into confusion : the aliment, instead of being assimilated, becomes more or less influenced by those laws which govern inanimate matter; fermentations and consequent eructations are produced ; distensions and irritations are engendered ; and sympathetic affections, occasionally of the most formidable nature and extent, where there is a ceptibility of their formation, become established.
But what is this condition of the nervous power requisite to insure those fibrous and secretory, those muscular and membranous actions, which are necessary to the production of chyme and chyle from the various substances received into the stomach? Dr. Wilson Philip has endeavoured to reply to this question by an appeal to experiment.
Far be it from us ever to countenance for a single moment that wanton trifling with the feelings and lives of inferior animals which the ultra zeal of physiological investigation has been too much disposed to indulge in ; but we cannot help considering the result of some recent experiments made by the individual to whom we have just alluded, if not replete with all the consequence ascribed to them by the author, as at least highly important, not merely in a philosophical point of view, but also in their practical tendency. Dr. Philip • divided the eighth pair of nerves in the necks of three recently fed rabbits, and every precaution was taken to keep their divided ends asunder. One of these animals, when subjected to galvanic influence, remained singularly quiet, breathing freely, and with no more apparent distress than the twitches usually produced by electric action, which was in this case kept up without interruption. The other rabbits laboured strongly in their respiration. They were all three killed at the same period, and their stomachs successively opened. la the two non-galvanized animals, chymification had scarcely made any progress ; but in that which had been galvanized, the process appeared to have been completed.'
The inference which Dr. Philip draws from these and similar observations, is, that galvinism and the nervous power are one and the same thing; or, in other words, that the puzzling problem which has been agitated for ages, with respect to the quo modo of nervous agency, is at length. solved by these instances of substituting ihe electric for the nervous influence.
Much further investigation is requisite for the full establishment of the proposed analogy. We confess ourselves, howéver, to have been struck, from the first announcement of the propositions of Dr. Philip, with the superiority, to say the least, of his doctrines over all preceding speculations on the subject of nervous influence ; and we think the following remarks of Dr. Paris will be perused with much interest by all who have given their attention to the subject of animal electricity, and the mode of its excitation by acids. Dr. Paris's suggestions, we must do him the justice to say, are always conceived in the cautious but not sceptical spirit that should ever direct the researches of the philosopher; and they are uniformly conveyed in the phraseology of a gentleman and a scholar.
• It is not my intention in this work, to enter into any speculations with respect to the more minute changes which may be supposed to take place under this galvanic influence of the nerves. My determi. nation in this respect has been made in consequence of learning from Dr. Prout, that he has long been engaged in the investigation, and has arrived at some very curious and important results, which it is his intention shortly to give to the public. In the next place, such details would be wholly inconsistent with the practical objects of my present publication. I shall therefore conclude this part of my subject by observing, that most of the digestive products are acid ; the chyme is uniformly distinguished by this character; and if the experiments of Dr. Prout be correct, muriatic acid is always present in the stomach : we may therefore suppose, that the nerves of this organ have the power of decomposing the muriatic salts, and of transferring its alkali to some distant reservoir, perhaps the liver. The intestinal juices are also acid; the fæces, unless they have undergone a degree of putrefactive decomposition, redden litmus ; the urine, as well as perspirable matter, are likewise acid; and it is scarcely necessary to observe, that the whole product of the respiratory function is carbonic acid.'
Here we must pause, reserving the continuation of the topic, in reference to practical, dietetic, and medicinal considerations, for our ensuing Number.
Art. II. 1. Reminiscences of Michael Kelly, including a Period of
nearly half a century, with original Anecdotes of many distinguished Persons, political, literary, and musical. In two Volumes,
small Svo. pp. 716. London, 1826. 2. The Life and Times of Frederick Reynolds. Written by Himself.
Two Volumes, 8vo. pp. 819. London, 1826. THERE is a superabundance of this flimsy sort of auto-bio
graphy afloat at the present moment; and we have taken up these volumes as giving a fair sample of an ephemeral species of literature, sufficiently well adapted to meet the tastes of light and lounging readers, but supplying little interesting information to inquirers of a more fastidious temper. With regard to the volumes before us, the humbler title ushers in the better book. The ambitious Exhibiter of his · Life and Times' has given us but little of the latter, and, of the former, just such a sketch as, with the help of Champagne and grimace, might pass current as spirited and humorous, but, when lying on a Reviewer's table in the questionable shape of paper and print, is not likely to stir a muscle. Mr. Reynolds started as a tragic writer, just as some of the most grotesque comedians first trod the boards in all the glories of the buskin ; but he is better known in his own dramatic world as the author of certain nondescript productions, classing strictly under neither of the three divisions of dramatic composition. Of genuine comedy, Mr. Reynolds has not the smallest conception; wit he has none; humour in its genuine form never gives zest to his scenes: for these he has provided a showy, but inadequate substitute, in the incessant bustle of his characters, the vivacity of his dialogue, and a happy knack at placing his personages in ludicrous situations. His first comic production, the Dramatist, was his best ; and was, in particular, so great a favourite with the late king, that, during his reign, he commanded' it not less than twenty times. But these are not our affairs, and we must decline to follow. Mr. Reynolds through the vicissitudes of his career, convivial or dramatic. He appears to have led a gay and dissipated life; to have enjoyed, in consideration of high spirits and companionable talents, a large portion of this world's good things in the shape of wine, joyous society, and the res culinaria; and to be at present realizing the after-blessings of such a course, in the visitations of arthritic and nervous disease. In one point of view, his volumes are singularly instructive. They form an admirable commentary on the Proverbs of Solomon and the Book of Ecclesiastes; and they show, with impressive admonition, to what base and miserable uses men may put intellectual and immortal faculties. It will be scarcely believed by any