Protein

Griesinger in 1859 published an analysis of 225 cases of diabetes; and though only eight were his own and the others all from the litera ture, his contribution was valuable for clinical experiments and sound judgment. He compiled the first evidence indicating excess in sugars and starches as a cause of diabetes, but concluded that it could not be the most important cause, or many more persons and some entire races would have diabetes. He overthrew various current errors, but somehow convinced himself in painstaking experiments that diabetics may excrete large quantities of sugar in the sweat, as reported by several other authors. From the negative findings in necropsies, he regarded diabetes as generally a functional disorder. His most notable achievement was the demonstration, in three separate experiments on a single patient, of sugar excretion equalling exactly 60 percent of the protein of the diet.“ These facts, remaining constant under varied conditions, cannot be accidental; they seem much more to contain the law of the relation in which, in this individual on exclusive meat diet, the production and excretion of sugar stands to the quantities of ingested meat."

Although advocating the employment of vegetable diet in cases of diabetes of the second class, I do not wish it for a moment to be supposed that I agree with Piorry in thinking that the cause of death, even in this form of diabetes, arises from the loss of sugar; for, on the contrary, I think it springs from the inability of the body to assimilate the sugar it possesses. In such cases, therefore, I give vegetable food, not because it contains sugar, but because it possesses many of the other substances necessary for the purposes of nutrition, which neither exist in the same quantity nor in so easily an assimilated form in animal diet. 

It is well known from the reports of travellers among savage nations, that men restricted solely to animal diet must consume an almost fabulous amount in order to obtain sufficient of all the ingredients requisite in the processes of life. "We know, too, that an animal can be most effectually starved by limiting him to one particular element of food, although that element be even albumen. The benefits derivable from Piorry's plan of treatment, therefore, in my opinion, arise from the fact that when he gives sugar he at the same time ceases to restrict the patient to animal diet, and that in the mixed food they find many of the materials essential to life much more abundantly and in a more easily assimilated form than in animal diet. I shall now give a few typical cases illustrative of the two principal forms of diabetes. 

Diabetes from Excessive Formation. 

In the beginning of 1860 a young gentleman, aged 19, suffering from diabetes, was brought to me by his brother, a Medical Practitioner, who had detected the disease two year previously. This patient had already been under various systems of treatment. What appeared to agree with him best was animal diet, coupled with. small doses of chlorodyne. 

To look at the patient one would have thought that he was a perfectly healthy individual. His weight was 135 lbs. ; the appetite was moderate ; and the amount of urine passed was not at that time excessive. The object of bringing the patient to me, it appeared, was in order that I might, if possible, suggest some remedy to replace the chlorodyne, the constipating effects of which were anything but agreeable. On carefully inquiring into the history of the patient, the case appeared to be one of diabetes by excess, and the origin of the mischief could in some measure be traced to some irritation in the liver, which was painful at its lower margin, the pain being much increased on pressure. Having an intelligent Practitioner to deal with, I at once gave my view of the case, and explained how, as scarcely any two cases of diabetes are precisely alike, it would be necessary to try the effects of different forms of treatment in order to discover what would be best for this particular case. The following table is an abstract of the results : 

TABLE 

The average amount of sugar passed by this patient during the next six months being from fifty to sixty grammes (775 to 930 grains) and his -weight 156 pounds, a quantitative analysis of the sugar -was no longer thought necessary. I may add that-when I last saw the gentleman in August, 1864 (on the occasion of his bringing to me a poor lad, -whose case I shall presently relate), he looked in excellent health, being, as he said, -without any feelings of discomfort, although he had still to continue his medicine, for as soon as he neglected it, the sugar again increased.

In the next place we must consider the purposes achieved by the class of fats or hydrocarbons in nutrition. Liebig's views with regard to this subject also have been shown to be erroneous. He considered the function of fats to be entirely respiratory, and that by combining with oxygen, admitted into the system in respiration, they were consumed in the production of heat, and that the completeness of this combustion depended on the amount of inspired oxygen. But it has been observed that when an exclusive diet of fat has been taken, there has been less fat metabolised and less oxygen absorbed than in fasting, and also that, in certain circumstances, the whole of the albumen in the food is metabolised in the body, and the fat is appropriated to increase the body-weight ; an inversion of the formerly assumed roles of hydrocarbons and albuminates. From which it would appear that, under certain conditions, fat is split up into simpler bodies with greater difficulty than albumen, and must not, therefore, be regarded as the same easily combustible substance in the organism that it is outside. 

It is not, then, through the direct action of oxygen that the non-nitrogenous foods any more than the nitrogenous ones are split up into simpler products, but by the agency of the cellular tissues, and the oxygen enters into these products "little by little." Indeed, under the influence of fat tissue-waste is lessened, and, therefore, less oxygen is taken into the system ; less oxygen being abstracted from the blood by the products of metabolism. 

We thus see that one of the great purposes served by fat in the food is to diminish albuminous metabolism, and it is, therefore, regarded as an "albumen-sparing" food. "If flesh alone be given, large quantities are required in order that nutrition and waste may balance one another, but if fat be added the demand for flesh is less." (Bauer.) 

But the fats have also an important relation in the body to the production of force and heat, to body-work and body-temperature. While, unlike the albuminates, the metabolism of hydrocarbons is independent of the amount taken in as food, it is notably affected by bodily exercise, which produces little effect on nitrogenous metabolism. The fats, therefore, undoubtedly minister to force-production, and undergo destruction and oxidation in the process ; so that the amount of carbonic acid given off" during exercise is much greater than during rest. 

External temperature also influences the meta- bolism of the hydrocarbons, and therefore the amount of carbonic acid excreted ; the lower the temperature, so long as that of the body itself is maintained, the greater the metabolism of non-nitrogenous foods, and the greater the amount of carbonic acid discharged from the body. This is one of the chief means of regulating the temperature of the body, and keeping it constant. 

When, however, the temperature of the body itself is disturbed, as in fever, then the higher the tempera- ture the greater the waste of the non-nitrogenous, as well as of the nitrogenous, constituents of the body, and the greater the excretion of carbonic acid, as well as of urea. 

It is probably through the nervous system that the exteiThil temperature influences the metabolic processes in the body, and especially through the peripheral sensory nerves.

 It would appear that albuminates and fats are, to a certain extent, opposed to one another in their action on the organism, as the former increase waste and promote oxidation, while the latter have the effect of diminishing them, and this they do prbably by affecting the metabolic activity of the cells of the tissues themselves. It is a matter of common observation that fat animals bear privation of food better than thin ones ; in the latter, their small store of fat is quickly consumed, and then the albumen is rapidly decomposed. It is for the same reason that corpulent persons, even on a very moderate amount of food, are apt to become still more corpulent. 

The influence of fat in the storage of albumen is exemplified by the fact that if 1,500 grammes of lean meat be given alone, it will be wholly decomposed ; but if 100 to 150 grammes of fat be added, then it will yield only 1,422 grammes of waste. It has also been shown that the balance of income and expenditure of albuminates, although the amount taken in the food may be very small, is readily established as soon as one adds a certain quantity of fat. A dog who took daily 1,200 grammes of lean meat was observed to be still losing some of the albuminous constituents of the body ; whereas, with only 500 grammes of flesh and 200 grammes of fat, the nutritive balance was rapidly re-established. The same has been observed in man. Rubncr found that an individual taking daily 1,435 grammes of meat, containing 48.8 grammes of nitrogen, lost by the kidneys 50.8 grammes of nitrogen ; whereas another taking meat and bread containing 23.5 grammes of nitrogen, to which were added 191 grammes of fat, only eliminated 19 grammes of nitrogen on the second day of the diet ; so that a small quantity of albumen, when combined with fat, is sufficient to maintain the albuminous structures of the body. As a practical conclusion from these considerations, we should note, that if we wish to increase the weight of the body and add to its con- stituents, we must not rely on an excess of albu- minates, as these given alone only lead to increased waste ; but if we combine fats with albuminates in proper proportions, an appreciable increase of both the nitrogenous and non-nitrogenous constituents of the body can be maintained for a considerable time. 

We see, then, how a proper use of fat economises the albuminous elements of food and checks the waste of the albuminous tissues. Fat enters into all the tissues. By its decomposition and oxidation it yields muscular force and heat, and it is therefore largely consumed in muscular exercise. By its capacity of being stored up in the body as adipose tissue, it provides a reserve store of force-producing and heat- generating material which can be utilised as required. 

The supporting influence of fat under great muscular fatigue is strongly maintained by Ebstei : and it is stated that the German Emperor, in the war of 1870, recognised this fact by requiring that each soldier should have served out to him daily 250 grammes of fat bacon!

The three classes of proximate principles that are neces- sary to be understood in the intelligent study of the food- stuffs, and in the selection of the most efficacious diet in disease are best divided into three distinct divisions ; the inorganic, the CHO, and the CHNOS compounds, or a first, second, and third class. 

First. The inorganic substances, such as water, the phosphates, chlorides, carbonates, sulphates, etc., etc. These chemical compounds all enter the body under their own form, either alone or in combination with the other two classes. They are not oxidized or split up within the system to enter into the chemical formation of other com- pounds, but are united mechanically with the proteid group, in fact, their whole action is, as it were, mechanical. After having served their purpose to the body they pass out of the system with the excretions absolutely unchanged in their composition. All medicinal compounds of a corresponding compo- sition and nature probably act in a similar mechanical manner. 

Second. The CHO substances which have for their chemical composition the elements carbon, hydrogen, and oxygen only as fat, sugar, and starch. These substances are all oxidized or split up within the system, yielding heat, energy, lubrication, and rotundity only, and are finally eliminated from the body as carbon dioxide and water. The medicinal agents of like chemical construction probably are oxidized and broken up to yield their effects by a similar cycle of changes. 

Third. The CHNOS substances or those which have for their chemical composition the elements carbon, hydrogen, nitrogen, oxygen, and sulphur. The common representatives of this group are called proteids, or the albuminous parts of milk, eggs, meats of all kinds, which chemically and histologically include fish, lobsters, crabs, turtles, oysters, clams, etc., also poultry and game. The nitrogenous or albuminous parts of all plant life, which is now commonly called vegetable proteid, is included in this class. 

All these nitrogenous substances, irrespective of specific names, are somewhat slowly oxidized or split up within the system and are absolutely essential to form the different constituents of all the fluids, tissues, glands, and ferments of the body, being united mechanically in varying proportions with water and the mineral salts. 

When these proteid bodies are normally transformed, their excrementitious products are urea, uric acid, kreatinine, carbon dioxide, and water in certain and definite proportions. If for any reason there is an abnormal transformation along this line of proteid metabolism, the relative quantity of urea falls and the uric acid rises. By closely studying these urinary changes and intelligently interpreting them, there is furnished an almost exact key to the perfection or imperfection of the oxidization processes and the nutritive condition of the body. By this method of study it is positively known whether the food-stuffs are absorbed and properly utilized by the system or not. 

Another important phenomena to be remembered in connection with the oxidization of the proteid substances is the fact that a disturbance in their anabolism not only changes the relative proportions between the urea and the uric acid, but tends to develop an almost unlimited number of katabolins, some of which are perfectly inert, while others are as toxic and dangerous to life as the well-known cyanide compound prussic acid. 

The action of the CHNO medicinal agents can he explained largely upon the same principles and chemical laws that govern the usefulness of the proteid bodies. 

With an intelligent conception of these three classes of proximate principles and what results are obtained for the system by their perfect and what by their imperfect oxidization, a comparative table of the common substances rated as food-stuffs is instructive. This table subdivides each kind of food product into its three distinct classes of principles. The inorganic compounds, however, are subdivided into water and the inorganic salts, so that their true position may be more clearly elucidated and the whole subject made plainer. 

[[Table 1]] 

Having in this brief manner outlined the composition of the food-stuffs and intimated at the same time the absolute necessity of understanding thoroughly the chemical and physiological laws that control their usefulness within the system, it becomes possible to advance a step further and state the quantities necessary for the most perfect nutritive condition. 

It also shows clearly how, by indulging too freely in any kind of food or by an unwise selection of the various kinds of proximate principles, the digestive system is constantly overtaxed, assimilation imperfectly effected and a host of diseased conditions developed. These abnormalties are brought about in the most insidious and often almost inappreciable manner, until, in some instances, well-defined symptoms are established by which a distinct name can be applied to the condition before attention is attracted to the malady. In a much larger percentage of the cases, however, the symptoms presented are so vague and changeable that the most learned specialist cannot possibly name the condition and sharply define the abnormalty so that it can be differentiated from many other states of a similar nature. Yet it is perfectly clear to every one, patient and practitioner, that something is decidedly wrong with the physiological mechanism of the system. 

Briefly stated, it may be assumed that the following table, No. II., gives a pretty close and satisfactory basis how the first and second classes of proximate principles should be arranged as to the relative proportions needed of each, from bare subsistence up to the largest amount of mental and physical work. 

[[Table 2]]

Before advancing any further in this physiological problem of food and nutrition, it must be admitted that the oxygenating capacity of the system is a limited one — but, fortunately for the human race, it has a moderately wide margin. There frequently comes a time, however, when this margin is exceeded, which is usually brought about by eating too large quantities of all kinds of food or too freely of the CHO classes of food-stuffs — as fat, sugar, and starches — or of both. As a natural sequence one of three things of necessity follows. 

First. The respirations and circulation must be increased to supply more oxygen or the food-stuffs will be imperfectly oxidized. But Nature has set a limit upon the actions of the heart and lungs so that complete relief cannot be granted in this manner. 

Second. The red blood corpuscles must be increased in number or empowered to carry more oxygen, or the absorbed food-stuffs will be imperfectly oxidized. But here again Nature has set a limit upon the number and carrying capacity of these anatomical bodies so that relief in this direction is wanting. 

Third. The super-abundance of food-stuffs absorbed must be incompletely oxidized because the system has no means by which the extra amount of oxygen required can be furnished. This statement applies with special force to che proteid bodies on account of well-established chemical laws, which show that the CHO elements are quickly and completely transformed under all circumstances while the CHNOS are only perfectly transformed when everything is most favorable. The CHO compounds, as fat, sugar, and starch, are rapidly and easily oxidized, consequently they are the first elements to be changed, and they are also completely transformed into their final products ; this tends to leave a deficient quantity of oxygen to act upon and accomplish the more difficult task of carrying the nitrogenous com- pounds through their cycle of change and finally into perfect excrementitious substances. This defective supply of oxygen disturbs the perfect metabolism of the proteid bodies and produces an unlimited number of katabolins and furnishes a rational explanation for many, if not all, of the pathological conditions and symptoms that have to be treated. At least it is fair to assume that so long as the anabolic processes of the body are perfectly effected, no pathological lesion or abnormal symptom can be developed. Keeping constantly in mind the table indicating the relative proportions existing between the proteids and the CHO compounds, or the fats, sugars, and starches, and studying a little more closely the composition and comparative merits of the various food products, much valuable information is brought to light. 

First. It is found almost impossible to arrange a mixed or vegetable diet so as to obtain the requisite amount of proteid elements without at the same time taking more than the needed quantity of the CHO compounds, that is, without introducing more than can be safely utilized or oxidized. 

Second. It is found that with an exclusive meat diet composed of the ordinary average meat almost the exact quantities of both the CHNOS and CHO compounds can be obtained from bare subsistence up to that for forced work. Taking four ounces of pure proteid matter as the standard amount required in twenty-four hours to perfectly maintain the constructive forces of the system, the following tables are quite instructive, viz. :

 [[Tables 3-7]] 

Examples of this kind might be multiplied almost ad infinitum. With all of the tables, however, excepting Table No. VI., there is clearly shown a larger quantity of the CHO compounds than is found of proteid elements. This shows that with almost all kinds of food-stuffs and especially when taken in excessive quantities the system is liable to receive a superabundance of the CHO substances. The ease with which the requisite amounts of proteid matter can be rightly adjusted to meet the demands of the system is clearly demonstrated. These tables just as clearly illustrate that it is almost impossible to arrange any form of the mixed food-stuffs in such a manner that the system will not be constantly super- charged with the stimulating and non-nutritious compounds of CHO construction. 

TABLE VIII. 

This comprehensive comparative diet table, compiled and used by Prof. William H. Porter, of the New York Post-Graduate Medical School, has been worked out upon the atomic basis of the proximate principles, which enter into the construction of the ordinary food-stuffs. 

It proves quite conclusively that Professor Porter's animal diet yields all that can be obtained by the use of a mixed diet containing the three elements — proteid, fat, and carbohydrate. 

In fact, in the proportions as here given, it calls for the use of a little more oxygen than the mixed diet based upon the proportions given by Moleschott ; it also yields a little more carbon dioxide and water. 

When it is remembered, however, that in the egg and the ordinary run of good meat, the proteid element is always a little more abundant than the fat, this excess of oxygen used — when taking an ordinary animal diet — will not be required, and the increased amount of carbon dioxide and water will not be produced, but the total results in excrementitious products cast off and the amount of heat and so-called energy evolved will come so very close to the amounts obtained by using Moleschott's mixed diet, that the two are practically the same. 

The conclusion, therefore, is that the relative proportions of these two elements, proteid and fat, as commonly found in eggs, meat, and fish, come so nearly to the required physiological demands of the system that, in this class of food-stuffs, there is found an almost perfect standard for diet. By adding a very small allowance of bread and butter, it becomes absolutely perfect. 

These chemical facts, based upon the atomicity of the Sood elements, explain the higher nutritive vitality developed in the carnivora as compared with the herbivora and vegetable feeding classes. 

Again, in diseased conditions where the nutritive powers are severely overtaxed, the proteid and fat diet is especially serviceable, for by its use the expenditure of vital force in transforming the food-stuffs is kept at the lowest possible standard. Because, in the use of animal fat to the exclusion of the carbohydrates, the system is spared the necessity of laying out force and oxygen to convert the starch and various sugar elements into a diffusible glucose, and then into an alcoholic-like compound before they can be utilized by the animal economy for the production of heat and the so-called energy, which is finally computed in foot pounds of work accomplished. 

This great saving in vital force by the exclusive use of fat — to supply the CHO elements necessary to produce the heat and energy required — is unquestionably the exact factor that enables the system to effect the cure in all the pathological conditions, which otherwise could not be carried on to a complete recovery. 

These same laws make Kumysgen one of the most valuable food products ever produced, because it has been found, that only about one-half of the fat contained in milk is capable of being absorbed, and with the lactose converted into an alcoholic compound there is developed in Kumyss or Kumysgen, particularly in the latter, a partially predigested food-stuff which contains about equal quantities of proteid and fat in a state to be readily absorbed. This then corresponds exactly with the requirements found in Professor Porter's table, which consists of only proteid and fat. 

Practical experience has long since taught that this form of dieting was the only kind available in connection with the successful treatment of the acute diseases. 

This table is further a demonstration and confirma- tion from a chemical and physiological standpoint, of what has been so often repeated in a clinical way, that upon this purely proteid and fat diet, together with the administration of suitable medicinal agents, the most aggravated forms of digestive disturbances can be quickly removed, nutrition improved, and a healthy standard permanently re-established. They show conclusively that this form of animal diet yields the largest working power to the system for a given amount of food taken, and a similar amount of oxygen used to carry the food substances through their anabolic cycle of changes, and finally form and discharge from the body the resulting excrementitious products.

At this point, however, it may be well to mention that the standard amount of proteid matter taken, in the construction of all these tables, was 130 grammes — 4.5 ounces. Moleschott's original diet-table contained only 120 grammes or (4.2 ounces), but as almost all observers agree quite closely as to the amount of proteid material necessary to be used, and also as to the results obtained from its oxidization, the same quantity was used in all instances that a more exact comparison might be established. The chief difference of dispute, however, is in relation to the relative value of the fats and carbohydrates, and particularly in reference to the latter compounds. 

In trying to develop out of a purely vegetable diet, anything like the same amount of working power for the system that is obtainable by the use of Porter's or Moleschott's diet, almost double the amount of proteid had to be taken with the proportionate rise in the fat and starch as is contained in the vegetable chosen. 

To produce the same amount of work by using a vegetable diet necessitates the outlay of a much larger amount of oxygen, and the production and handling by the glandular structures of the body of an excessive amount of the nitrogenous excrementitious elements. These facts illustrate quite conclusively the manner in which the damage to the system is brought about by indulging too freely, or living exclusively upon a cereal or vegetable compound. 

The vegetable proteid in these tables is further given an undue advantage, to which it is not justly entitled, by crediting it with the same atomic formula as that possessed by an animal proteid ; since the nitrogenous element found in plant-life contains a much larger number of nitrogen atoms, and consequently requires more vital force and oxygen to digest and assimilate it. This naturally decreases rather than improves the nutritive value of the proteid compound of vegetable origin. 

An average of a compound fat molecule is taken as the working standard in all these tables. 

Attention is also directed to a probable error in the rating of the heat-producing power of the carbohydrate. It is & commonly stated, that the comparative oxygenating capacity of a carbohydrate and fat is as one to two and one-half, but by their chemical atomicities, it is as one to thirteen, or thirteen and one-half in favor of the fat. 

That such an error exists in the computations in Moleschott's standard is sustained by a comparative study of the atomicities of the food-stuffs used in both Porter's and Moleschott's diet tables, and of the amount of oxygen required for complete oxidization in both instances. In the former, or Porter's proteid and fat diet table, a little more oxygen is needed than is necessary in Moleschott's mixed diet* yet it is claimed that in the latter instance 393,170 kilogramme-metres or 54,358 more foot pounds of work is produced. This, however, is directly opposed by the smaller quantity of oxygen used in the oxidization processes. When this error in work, produced out of the carbohydrates in Moleschott's diet, is corrected in accordance with the difference in atomicity and the amount of oxygen used between the fat molecule and the carbohydrate molecule represented as glucose, and a computation is made in accord with the correction, a slight difference in work produced when living on a Moleschott's or Porter's diet, is found to exist. The increase in work produced, however, is now found to exist in connection with Porter's diet and is in accord with the larger amount of oxygen used, which makes atomicity, oxygen used, and work produced correspond, while the reverse was stated in the calculations formerly made in connection with Moleschott's diet. 

If this error be true, as it appears to be, the profession have been sadly misguided in all their attempts in the construction of diet tables starting with Moleschott as their standard. 

On the other side, if these chemical and physiological laws be true, as based upon the atomicity of the proximate principles, by carefully considering the percentage composition of each food product to be used, exact results can be obtained. Another point to which attention is called by Dr. Porter is this, that the factors 1.812 and 3.841, which are used in computing the kilogramme-metres in Table VIII., are taken from Frankland — Philosophical Magazine XXXII., and are those which are generally quoted in all scientific works upon physiological chemistry and upon diet. 

In studying the proximate principles, however, by the atomicities, and considering the amount of oxygen required to completely transform a fat molecule into its final products of excretion water and carbon dioxide and a proteid molecule into its final products of excretion — urea, uric acid, kreatinine, carbon dioxide, water, etc. — it is found that only eighteen (18) more oxygen elements are used in the complete oxidization of the fat than in that of the proteid molecule. The computed amount of work performed by the oxidization of the fat molecule is found to be 530 foot pounds as compared to 250 foot pounds for the complete oxidization of the proteid molecule. This makes the eighteen (18) more elements of oxygen used in transforming the fat molecule result in the production of 280 more foot pounds of work than is obtained from the eighteen less used in the proteid. 

From this a decided discrepancy is quite evident between the results obtainable by former calculations and those based upon our modern chemical atomicities. 

However, for an illustrative and comparative study of the working power obtainable from the use of the various food-stuffs, this table is still of great value, as the same figures are used in each and all the calculations. 

As these same factors, 1.812 and 3.841, appear in all the modern scientific works, they were retained in the arrangement of this table, but not without appreciating and calling attention to this discrepancy when the computation is based upon the atomicities of the food elements used, the amount of oxygen required, and the results obtained. 

Again, it must be remembered that the proteids are not directly transformed into their final products, but undergo a series of intermediate changes, all of which require the use of oxygen and must of necessity yield more or less heat and energy, so that all our estimates are approximate. 

When upon Moleschott's diet with the proteid substances raised to the common standard of 130 grammes and the carbohydrates rated in accord with the correction previously noted, it requires 36,115 oxygen elements to produce 678,270 kilogramme-metres or 93,773 foot pounds of work. 

When upon Porter's diet of proteid and fat, it requires 38,415 oxygen elements to produce 734,890 kilogrammemetres or 101,602 foot pounds of work. When upon a purely vegetable diet that will yield anything like the requisite amount of work that can be obtained by using Moleschott's or Porter's diet, it requires 47,191 oxygen elements to produce 742,018 kilogramme-metres or 102,587 foot pounds of work. 

To obtain the 63,748 more kilogramme-metres or 8,814 foot pounds of work out of the vegetable diet as compared with Moleschott's diet, it requires the expenditure of 11,076 more oxygen elements. 

To obtain the 7,128 more kilogramme-metres or 985 foot pounds of work out of the vegetable diet as compared with Porter's diet, it requires the expenditure of 8,776 more oxygen elements. The vegetable diet in both instances yielding an excessive amount of nitrogenous excretory matter, carbon dioxide, and water. 

A careful study of Table II. and VII., and Porter's diet in Table VIII., proves beyond a question of doubt that upon an exclusive diet of our ordinary average meat alone very nearly the required proportions of the proteids or CHNOS compounds and of the fat or CHO element can be established. 

The only defect in the perfection of Table VII. and VIII. is found in the saline column, which contains much more mineral matter than perfect physiological laws indicate are required. This excess in saline or inorganic compounds, however, appears to be true in all kinds of food products — that is, if the proportion of salts in the milk is taken as the guide for a working basis. The reason for looking upon the amount of salts in the milk as the guide to the maximum quantity required is based upon the fact that during the infant period of life, where milk forms the only source of food supply, bone formation is most rapidly progressing, and the amount of mineral matter needed by the system is at its height and much larger than at any other period of life. The bones continue to grow and become fully and perfectly developed with the ordinary quantity of mineral matter contained in the milk. 

Physiology also teaches that a little less than one ounce of mineral salts are required daily by the system, but in all the tables given, except the one containing milk alone, the amount of salts is fully up to or more than an ounce. 

The only great objection that can be raised to an exclusive meat diet is the lack of variety, but that is quite easily adjusted by varying the kinds of meat used. The perfection of the proportionate composition of the proximate principles when using a meat diet, the smaller liability to imbibe an excessive quantity of any one kind and the little danger that there is of taking an excess of the CHO or stimulating and non-nutritious compounds, clearly establishes the fact that in meat we approach the nearest to an ideal food. 

If attention is turned for a single moment to the lower orders of the animal kingdom, it is quite apparent that the most supple and intensely powerful organisms are found among the carnivora only. This tends to substantiate the high utility of the meat diet. Another interesting point is the almost universal absence of tuberculosis among meat-eating animals, while the vegetable-feeding class are specially prone to suffer from this fatal malady.