creditable to the skill of our author. He cannot, indeed, claim any origi nality as to the discovery of the connection that so often exists between ulcerative inflammation of the lower segment of the uterus and Sterility: for on this point, as indeed on most others treated of in the volume before us, he has been quite anticipated by Dr. Henry Bennett, to whom unquestionably belongs the almost exclusive merit of having, within the last few years, drawn the attention of the profession-in this country at least to the important part which this morbid state plays in the production of some of the most troublesome complaints to which women are subject, both in the pregnant and the unimpregnated condition. Mr. Whitehead seems, rather strangely, to be but very imperfectly acquainted with the results of his predecessor's researches. The following propositions, with which Dr. Bennett concluded a series of very interesting and valuable papers which appeared in the Lancet during the course of last year, may be appropriately introduced here. Their general accuracy has been strikingly confirmed by the subsequent enquiries of our author as well as of other observers. 66 1. Inflammatory ulceration of the uterine neck is not an uncommon disease in the gravid uterus, although hitherto entirely overlooked by uterine pathologists and by accoucheurs. "2. When this disease exists in the pregnant state, its symptoms are the same as in the non-pregnant condition, but obscured, and more or less modified, by the pregnancy. 3. It is a frequent cause of disordered health during pregnancy, or of laborious pregnancy.' It is also one of the most frequent causes of Abortion, both in the early and in the later months of pregnancy. It may occasion abortion, either directly, by reflex action, or indirectly, by giving rise to disease of the avum or placenta, or to uterine hæmorrhage. "4. The instrumental examination of females labouring under inflammatory ulceration of the cervix during pregnancy is unattended with any risk, either to the mother or to the foetus; and it is absolutely necessary, in order not only fully to recognise the disease, but also to treat it, "5. The treatment of these forms of uterine inflammation must be governed by nearly the same rules in the pregnant state as in the non-pregnant state. A properly conducted treatment is nearly always successful in preserving the life of the child and the integrity of the pregnancy, as well as in curing the inflaminatory and ulcerative disease. It is also the only means we possess of warding off the imminent danger of abortion to which the patient is exposed. "6. This form of uterine inflammation being, generally speaking, the cause of those repeated and successive miscarriages which prevent females giving birth to a living child, it is only by curing it that we can hope to make them bear the product of conception to its full period. 66 7. The serious inflammatory and hæmorrhagic symptoms which sometimes follow abortions are generally occasioned by unrecognised inflammatory ulceration of the uterine neck. On investigation, it often becomes evident that this disease existed previous to the abortion, and occasioned it. The same remark may apply to some cases in which the above-mentioned symptoms precede and follow labour at the full time, as ulcerative inflammation of the cervix in the pregnant state is by no means necessarily followed by abortion. "8. Although inflammatory ulceration of the cervix seems generally to be a cause of Sterility, yet, as will appear from the above essay, there are frequent exceptions to the rule. In some females, the tendency to become impregnated is so great that no amount of uterine disease appears to prevent conception taking place," 1847] Liebig and Mulder on Animal Chemistry. 405 In taking leave of our author we must again enter our caveat against all uncalled-for or unadvised use of the speculum in the complaints of females. Though most valuable in many cases, and absolutely necessary in others, it need scarcely be said that the employment of this means of exploration may become the source of no trifling mischief, in more ways than one. We cannot but think that Mr. Whitehead has set a very questionable example to his younger brethren in the profession, by his frequent adoption of it in that condition of the female system, when the instinctive feelings of Nature shrink from exposure; nor can we think very highly of an author's feelings of decorum, who could deem it at all necessary or proper to proclaim to the public his belief" that the danger of copulation during the period of menstruation to be in a great measure assumed and fanciful, or, at all events, to be far less imminent than has been represented." If Mr. Whitehead's volume reaches a second edition-which we think not unlikely, considering the value of a great part of its contents-it must undergo a very thorough revision, in the way of retrenchment, compression, and collation with what has been done by other writers in the same department of pathological enquiry. We would particularly direct his attention to a very valuable paper from the pen of Dr. Evory Kennedy in our excellent cotemporary, the Dublin Medical Journal, for last May. I. RESEARCHES ON THE CHEMISTRY OF FOOD. By Justus ALTHOUGH these recent works, or rather portions of works, of the two celebrated rival chemists, deal too much in special details to admit of lengthened notice, valuable as these may prove for the purposes of reference, at least when some of the statements they contain have been corroborated by farther investigation, they also refer to matters of a more general character which may advantageously be adverted to here. While there is such discrepancy in important statements made as to the results of minute analyses by men who should be incontrovertible authorities upon subjects to which the whole energies of their lives have been devoted, we may be well excused detailing that portion of their labours, in the hopes that renewed investigation, patiently and charitably conducted, may reconcile differences. Professor Liebig commences his Essay with an introductory chapter upon the "Methods of Investigation in Animal Chemistry;" in which he endeavours to demonstrate that, if the active spirit of chemical research which has now been going on for the last ten years is so barren in actual and assured results, this has arisen principally from the faulty mode in which the investigations have been carried on, in consequence of which erroneous, insufficient and premature conclusions have been arrived at. As an example of these, Mulder's Proteine Theory is put prominently forward, in a tone of assumed superiority, not altogether becoming one who once acknowledged its validity, or very well calculated to heal breaches of good understanding already made. One source of error arising from the isolation of the researches of the chemist from those of the physiologist and pathologist, is thus touched upon. "In modern times this method (hypothetical systems of medicine) has been abandoned as entirely unproductive; but, on the other hand, men commit an error not less grave, inasmuch as, instead of acquiring by their own researches the knowledge necessary for the solution of their difficulties, they leave this duty to others, who, fully occupied with the cultivation of their own branch of science, have neither interest in the questions to be solved, nor inclination for the task, From the chemical analysis of blood, of urine, or of a morbid product, they expect an aid which these analyses can never afford, as long as the results of the chemist are not brought into the true connection with the conditions which they are to explain, or with the causes which have produced these conditions. All the new facts daily ascertained by the chemist are regarded by pathologists as being exactly those which are of no direct use to them, because they have no clear idea of that which they require; because they are unable to connect with these chemical discoveries any question to be solved, or to draw from them any conclusion. "What an inconceivable delusion, what a confusion of ideas must exist, when a physician thinks, that from the complex results of an analysis of the blood, he can draw a conclusion as to the nature and the cause of a disease, and can found on this a method of treatment, when we have not yet advanced so far in physiology as to bring into relation with the digestive process one of the simplest chemical facts, namely, the absence of alkaline phosphates in the urine of the herbivora! What pathologist has ever yet attempted to fix and define the notion of bad or spoiled food, in its full signification, by means of a logical comparison with good and wholesome food? and yet the former are regarded as the proximate causes of diseased conditions. I really admit, that for such an investigation chemical knowledge is indispensable; but the investigation itself has no value in reference to chemistry, and constitutes no object of research for the chemist, as such. "From this state of things, which depends on the want of connection between the labours of chemists and those of physiologists, it has happened, that Animal Chemistry, during the last ten years, has gained little more than a more accurate knowledge of those compounds which the animal organism applies to no further purpose in its economy; and that, at the present time, it seems as if all the wonderful properties which it exhibits were produced only by means of albumen, fibrine, gelatine, some cerebral or nervous matter, and a little bile. It is universally felt, that we are as far from a true animal chemistry as the anatomy of the last century was from the physiology of the present day. Indeed the animal chemistry of our time cannot be compared to modern anatomy, since microscopic researches have established the existence of structures which had entirely escaped the earlier investigators; of structures, as is now known, on which alone the function of those formerly observed depends." P. 5. The knowledge derived from ultimate Analysis which has of late been so industriously pursued, is here shown to have been more apparent than real-the formula thus accumulated too often proving data of little worth. 1847] Insufficiency of Ultimate Analysis. 407 "About ten years since, the ultimate analysis of organic bodies furnished physiology with a result highly important, in order to the easy understanding of the digestive or nutritive process, by demonstrating, that fibrine, albumen, and caseine have the same composition. Misled by this result, many chemists thought that the chief problem to be solved by chemistry was to ascertain, by ultimate analysis, the composition, in 100 parts, of all the constituents of the body; and thus many were induced to act on each of these constituents, without a more minute study of its chemical relations and its properties, with alcohol, ether, and acids; and with the aid of the known resources of organic analysis, to determine the percentage of carbon, nitrogen, hydrogen, and oxygen. They believed that they had thus, by means of these numerical results, done a real service to physiology, although the only addition thus made to the name of the substance analysed was an empty formula, of the accuracy of which there was no evidence whatever. Now that we have been for ten years in possession of these formulæ, every one must perceive that we have made no real progress. The cause of this is obvious to all who know the true value of ultimate analysis. Ultimate analysis is a means of acquiring knowledge, but is not itself that knowledge. Even supposing, what no one will seriously maintain with regard to the constituents of the animal body, that analysis had made us acquainted with the exact proportions in which their elements are united together, yet this knowledge gives us not the least information as to the arrangement of these elements, or the way in which they group themselves, under the influence of chemical agencies. Now it is the knowledge of both these things together which alone can lead us to definite views as to the part which these compounds play in the vital processes, or the changes to which they are subjected up to the period of their expulsion from the body; and this is essentially the problem which Chemistry has to solve in reference to the vital process. "Ultimate analysis, by itself, has this peculiarity, that in the case of very complex substances it cannot secure the chemist against errors, because there is no other control for the accuracy of the analysis than the analysis itself; and because the errors are equal at different times, and escape notice when we cannot change the methods of determining the individual elements. Now there is as yet no means of determining the weight of carbon otherwise than in the form of carbonic acid, or that of hydrogen otherwise than in the form of water. "The only way to attain an accurate expression for the composition of those substances, which, like the constituents of the animal body, contain a very large number of elementary molecules in the complex atom of the compound, is to endeavour to resolve it into two or more less complex compounds, and to compare the composition and the amount of these products with those of the body from which they have been derived." P. 12. The main part of Liebig's work is occupied in detailing his analytical investigation of the Constituents of the Juices of Flesh. After alluding to the crude views formerly entertained respecting the presence of Lactic Acid, he dwells at some length upon the properties of Kreatine discovered by Chevreul in 1835 to be a peculiar crystallizable body obtainable by boiling flesh with water. Since then other chemists have obtained it in small quantities, while others failing to do this have considered its presence accidental. Liebig details the process by which it may be obtained, providing largish quantities are operated upon. From 8 to 10 lbs. of flesh must be employed, and even from this, after the coagulation of the albumen and colouring matter, soluble matters to the amount of 4 ozs. only will be obtained for investigation, and that but by the use of a good press. The fluid obtained possesses an acid re-action, and even in those animals in which it has only been obtained in conjunction with blood, the alkali of this does not neutralize the free acid of the flesh. "Indeed, I believe, that in most animals, if we suppose the whole mass of blood in the vessels to be mixed with the whole fluid of the muscles, the mixture would retain, not a neutral or alkaline, but an acid re-action." The free acid is removed by means of a solution of baryta, giving rise to precipitates of the phosphate of baryta and of magnesia. The filtered fluid is then gently evaporated until the crystals of Kreatine are deposited. The amount of this substance produced varies not only in the flesh of different kinds of animals, but even in animals of the same class-the quantity being always much less in fat flesh than in lean flesh. 1000 parts of the filesh of lean fowls yielded 3.05 of Kreatine: 1000 of the horse 0.72: 1000 of the ox 0.697. Obtained and purified Kreatine is neither acid or basic. When Kreatine is dissolved in heated strong hydrochloric, sulphuric, phosphoric, or nitric acid, and the solution evaporated, crystals are obtained which are very soluble in alcohol, which those of Kreatine are not. By this contact with the strong mineral acids a portion of these enters into combination with the Kreatine, and a new body, of totally different chemical properties, a true organic alkali, and termed by Liebig Kreatinine is produced. This is far more soluble than Kreatine; and in its chemical character is quite analogous to ammonia. The compound discovered in the urine three years since by Pettenkoffer contains the same proportions of carbon and nitrogen as do Kreatine and Kreatinine; and a repetition of Pettenkoffer's analysis by Liebig shows this substance to be a mixture of Kreatine with a little Kreatinine: and although neither of these bodies exist in great amount in the urine, yet may they be more conveniently procured from it than from flesh. After describing the Salts of Kreatinine, Liebig gives an account of another organic base termed by him Sarcosine, produced by adding to a boiling saturated solution of Kreatine ten times the weight of crystallized hydrate of baryta. Ammonia is disengaged and carbonate of baryta precipitated, while a colourless fluid containing Sarcosine and caustic baryta is produced. "If from the elements of crystallised kreatine we subtract those of sarcosine, there remains a formula exactly identical with that of urea. There remains 1 eq. Urea = C2 N2 H4 O2 "It is consequently obvious that, in the decomposition of kreatine by baryta, carbonic acid and ammonia are secondary products derived from the decomposition of urea. I have ascertained that a solution of urea in barytic water is resolved by long boiling into carbonate of baryta and ammonia with the same appearances as those above described; and I have also ascertained that urea is present in the liquid when kreatine is boiled with baryta, if examined before the whole of the kreatine is decomposed." P. 75. By the agency of alcohol upon the liquid from flesh, whence all the Kreatine has been deposited, crystals of an acid, termed by Liebig Inosinic, may be procured. After describing this and the compounds it forms with baryta, potash, &c., and detailing a simple process by which Kreatinine |