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weight, hygrometry, endosmose; and the chemical phenomena of affinity, attraction, of composition and decomposition. But whilst inorganic substances implicitly obey the general laws of nature, organised bodies exert a constant reaction against their destructive influence, in virtue of a constitution which is peculiar to them, and which, endowed with solids, liquids, tissues, organs, and systems, give rise to functions which in their aggregate constitute the incomprehensible phenomenon named life.

Life, then, is the continued and prolonged struggle of the laws of individual against those of universal nature; and the amount of vitality is proportioned to the degree of superiority of the first over the second. Without attempting to investigate the phenomena which accompany the higher functions of animal life-phenomena which as yet have baffled all scientific attempts, and remain an apparently impenetrable mystery-our author confines his researches to those immediately dependent on the material conditions of existence, or those of organic life only, and remarks, in the words of M. Dumas, “To others belong the care and privilege of developing the noble faculties of the human intelligence ; our more humble task must confine itself to the field of the physical phenomena of life.”

The first chapter is devoted to the phenomena of oxidation and nutrition, and is divided into many sections. When treating of the influence of oxygen in the transformation of the tissues, much stress is laid upon the power gained by the extended surfaces arising from the extreme porosity of the tissues, and some good examples brought forward in illustration; among others, an experiment by M. Dumas, showing that sulphuretted hydrogen is very easily oxidated and transformed into sulphuric acid, simply by the influence of moist clothes or sheets.

Another interesting experiment of M. Millon is quoted, showing the power that hydrocyanic or prussic acid possesses of arresting the oxidation of certain chemical substances. For example, when a few drops of this acid are added to a mixture of iodic and oxalic acids, the decomposition of the latter, which usually rapidly ensues, is entirely arrested ; and our author supposes that a similar explanation may account for the terrific and rapidly-poisonous effects which ensue when this acid is brought in contact with the living body. The application of the results obtained by M. Millon to the explanation of the toxicological effects of prussic acid, is by no means novel. We have for many years been accustomed to compare the two phenomena when explaining to our class the physiological action of this drug. In this section are given most of the phenomena of change which different substances undergo in passing through the animal economy; but these being met with in many other chemical and therapeutical works, need not detain us.

After devoting a few pages to the consideration of the ferments met with in the vegetable and animal kingdoms, in which we find little or nothing having any pretensions to novelty, the phenomena of the digestion and absorption of those alimentary substances which are indispensable to nutrition, is discussed, under the following heads:

1. Vegetable matters, or hydrocarbons; as sugar and starch. 2. Nitrogenized, or albuminous substances; as albumen, casein,

gelatin, and gluten. 3. Fatty bodies; as fats and oils.

The views of M. Mialhe upon the digestion and assimilation of the first class of these bodies are somewhat peculiar; and as they bear particularly upon the study of the pathology of certain forms of disease, and would, if adopted, greatly influence the treatment, we shall not scruple to devote some little time to their consideration. Our author, in the first place, states that crystallizable, or rather cane sugar, when injected into the veins of an animal, is thrown out in the urine without having experienced any change in its passage through the system; whereas if glucose, or starch sugar, is substituted for cane sugar, it is not eliminated by the kidneys, nor, after a short time, is it found in the blood ;-facts which show that cane sugar is not immediately assimilable, but that it is necessary that a conversion into glucose should first ensue. This conversion takes place in the digestive organs, by means of the acids and ferments which it there meets with, and may be readily imitated out of the body by the use of weak acids or certain nitrogenized matters. Mialhe thence concludes, that glucose and the allied sugars alone are susceptible of being used in the secondary assimilation, and that cane sugar, if it enter the blood as such, acts only as a foreign substance, and is destined for elimination. When we speak of glucose and the allied sugars, those only are intended to be understood which are at once decomposed by caustic alkalies and alkaline earths into the coloured acids, and which possess the power of reducing copper to the state of the suboxide when the solutions of the protosalts of this metal-such as those known by the names of Barreswill's, Trommer's—are employed. This group includes not only glucose, but also the sugars from acid fruits, diabetic sugar, &c. Amylaceous matters are next shown to be converted into glucose in the digestive passages, and some pages are occupied in discussing the causes of this change, and the author endeavours to establish the correctness of his own discovery, published in 1845, namely, that this change is effected by aid of the saliva. Our space, however, will not permit us to enter into the merits of this question, as we are about to discuss more particularly another section of the chapter, relating to the destruction of sugar in the animal economy.

With regard to the source or origin of sugar in the system, M. Mialhe appears to disregard altogether the researches of Bernard, who has demonstrated that the liver is the chief sugar-producing organ in the body, and that it is efficient to generate all that is necessary, even from food entirely deficient in saccharine or amylaceous matters, and to agree with those who have endeavoured, unsuccessfully we believe, to show that the sugar found in the liver of an animal who has been fed for a long time on an exclusively meat diet, is derived from the traces of this principle said to be contained in flesh and eggs. The arguments in favour of Bernard's views, supported by experiments apparently

incontrovertible, have been placed before our readers so fully in our January number, as not to need repetition here.

Whatever be the source of sugar, whether it be derived from the transformation of amylaceous matters by the action which takes place in the alimentary canal, or whether it be secreted by the liver, the question next arises, Why do we not meet with it in the different excretions, in the healthy condition of the economy? Why does it disappear so rapidly from the blood ? Is it destroyed, to serve other uses in the system? Undoubtedly, in the healthy state at least, it is decomposed and converted into some other compound or compounds, and eliminated in these new forms by one or more of the excreting channels ; it becomes, however, a question of great interest, as bearing directly both on the pathology and treatment of diabetes, to determine whether diseased states occasionally occur in which this change does not ensue; and again, whether such a condition exists in cases where the phenomena of glucosuria are exhibited.

We shall find that Mialhe is a strong supporter, perhaps the originator, of this view, and endeavours to support it by chemical analogies and some very few clinical facts; we must, however, here express our opinion of M. Miahle, derived from the perusal of his work,-he is evidently but partially acquainted with physiology, and still less with clinical medicine, and he often gives very undue weight to certain relations which he thinks to exist between chemical changes occurring out of the body, and those which take place under the influence of the more complicated and less understood chemistry of vitality. But to return to our subject; it is well known that under the influence of alkalies in their free state or in that of carbonates, glucose is decomposed by heat, and resolved into dark-coloured compounds, consisting of melassic, ulmic acid, &c.; but it is not so altered when alkaline phosphates, even those having an alkaline reaction, are made use of. Again, this form of sugar possesses deoxidizing powers, and is capable of decomposing certain metallic salts, especially those of copper, reducing them to the condition of suboxide, when an alkali is present; M. Miahle, taking these chemical facts, endeavours to compare them with the phenomena which ensue in the interior of the organism : he states, for example, that some metallic salts, as the ferriocyanide or red cyanide of potassium, injected into the veins, passes into the urine in the state of the ordinary yellow salt or the ferrocyanide; that in cases of poisoning by the protosalts of copper, the metal is found in the tissues in the form of suboxide, and that corrosive sublimate is converted into calomel, and these changes are ascribed to the presence of glucose in the blood, and said to be aided by the administration of this substance ; it is also shown that glucose is not able to absorb oxygen from the air, unless previously transformed into other compounds, and that this necessary change takes place from the presence of alkalies or their carbonates.

M. Mialhe asserts, that in the normal state there exist considerable amounts of alkaline carbonates in the blood, and therefore the glucose finds in that fluid all the conditions necessary for its oxigenation and transformation. The following he supposes to be the order in which the phenomena ensue: the sugar enters the blood, decomposes the alkaline carbonates, forms with the bases new salts, glucosates, setting free the carbonic acid ; the salts thus formed having but slight stability, are rapidly transformed into glucic, ulmic, and formic acids, or rather salts of these acids, which absorb oxygen, undergo a species of combustion, and give rise to water and carbonic acid as ultimate products. According to this view, the destruction of glucose is a phenomenon closely allied to combustion, and it is by means of the alkalies of the blood that this change is effected, and sugar is able to serve as a respiratory agent or element. From this point M. Mialhe passes at once to the consideration of diabetes, for if, says he, the glucose from any cause ceases to undergo the above-named changes, the blood must necessarily become charged with this principle, which, acting as a foreign body, is afterwards eliminated by different glands, more especially the kidneys, giving rise to the secretion of large quantities of saccharine urine, thus constituting the disease known by the names of glucosuria or diabetes.

After examining the various hypotheses which had been proposed to explain the nature of this obscure affection, our author was led to think that it was to be sought for by investigating the phenomena attending the destruction of the sugar in the system, and as the result of his search, came to the conclusion that the true cause is a deficiency of alkali in the blood ; for, he remarks, the digestion of amylaceous matters takes place in the same way both in the diabetic subject and the healthy individual, in both there is the same transformation of starch into glucose under the influence of the saliva and pancreatic juice; but in the latter, the glucose is further altered and decomposed by the alkalies normally present in the blood, whilst in the diabetic patient there is an absence of this destruction of glucose from a want of alkalinity ; this deficiency of alkali is ascribed to several causes, as the abuse of acid drinks, a too exclusively nitrogenized diet, and suppressed perspiration.

M. Mialhe certainly brings forward many arguments and illustrations which appear at first to be highly favourable to his views: for example, he instances that in the blood, when in a healthy state, glucose cannot exist or remain undecomposed, as it possesses alkalinity; whereas in the sap of vegetables, which is either neutral or acid, sugar is normally present; that as a plant watered with a slightly alkaline solution ceases to produce sugar, or rather destroys it as soon as it is formed, so in the animal economy, if by accidental or other circumstances the acid secretion of the skin becomes arrested, or if by the daily taking of acid substances, or substances easily convertible into acids, the blood loses its alkaline qualities, being saturated by the acids, it approaches in character to the condition of sap, and then the existence of sugar in the blood becomes possible, and the diabetic condition is induced. Our author states that the only important objection which has been opposed to his views, is the fact that the blood of diabetic patients is never either neutral or acid, but always preserves its alkaline reaction. He answers this by stating, that it is difficult to tell the amount of alkalinity of the blood, and again, that part of the alkaline reaction of this fuid is derived from the presence of alkaline phosphates which possess no power of decomposing glucose; he is therefore inclined to consider that the carbonates are deficient or absent, the phosphates remaining intact, thus preventing the fluid from exhibiting any but an alkaline reaction. M. Mialhe, however, allows that other circumstances besides the insufficiency of alkaline carbonates, may prevent the combustion of sugar, and induce at least temporary glucosuria, and hence is inclined to agree with M. Reynoso, as to the influence of a deficient performance of the respiratory function.

In the treatment of diabetes, M. Mialhe strictly acts up to the indications dictated by his hypothesis, and proposes, above all, the use of alkaline remedies ; under the influence of these agents, he states that the sugar in the urine quickly diminishes, and even disappears altogether. The alkalies prescribed are lime water, magnesia, Vichy waters, and the bicarbonate of soda ; at the same time he makes use of alkaline and vapour baths, flannel, friction, exercise, and sometimes sudorifics; he also orders a diet restricted at first as to the amylaceous principles, but these are gradually increased in amount according as the system is able properly to assimilate them; he reprobates the exclusive use of an animal diet, as generating an undue proportion of acids in the system. One case of a diabetic patient, who was treated on M. Mialhe's plan, is related, and as it exhibits a somewhat remarkable disappearance of sugar from the urine, we will present an abstract of it to our readers.

M. Garofolini, an Italian professor of music, had resided in Paris for several years; he formerly enjoyed excellent health, but latterly had been suffering from pain in the renal regions and from colic, causing frequent desire to pass urine and likewise some tenesmus. He occasionally took Vichy water, which rapidly removed the symptoms, and within a month his health appeared to be re-established. He remained well for two years; but after that time, during the intense heat of the summer, he was tormented with great thirst, to allay which he drank a very large quantity of acid drinks, and partook of acid fruits, but without relief to the thirst or the constant dryness of the mouth. The desire to pass water became more frequent, and the urine much larger in quantity, appearing even more in bulk than the liquids taken during the same period of time; there were also a feeling of general illness and great muscular debility, progressive emaciation, feebleness of vision, loss of virile power, and obstinate constipation; he then came under the cognizance of M. Mialhe, The urine was at once examined, and found to have a density of 1040; treated with potash it gave a dark-brown colouration, indicating the presence of a large amount of sugar. He was ordered to abstain entirely from acidulated drinks, and to take during the twenty-four hours 20 grammes (308 grains) of bicarbonate of soda, and 5 grammes (77 grains) of calcined magnesia ; also two bottles and a half of Vichy water. The next day the urine had only a density of 1026 in place of

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