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Boston Medical Library



£ - 9





Dental and Oral Science.








MA ^ Iff 9 1


Angle, Bdwabd H., D.D.S. Atkinson, Charlks 6., D.D.S. Bakeb, Djl H. a. Bazin, Dr. J. A. Blair, L. P., D.D.S. Brtan, Dr. L. C. Bruob, James A., D.D.S. BuLKLET, T. Duncan, A.M.,

M.D. Btrnes, B. S., D.D.S. Cooke, William P., D.M.D. Curtis, G. L , M.D., D.D.S. DoDOE, Henry N., M.D., D.D.S. DwiNELLE, W. H., M.D., D.D.S. Fellows, Dr. D. W. Gates, Willl^m H., D.D.S. Gibbon, Dr. Kasson C. Hamilton, Dr. H. F. Howe, J. Morgan, M.D., D.D.S. Jackson, V. H., D.D.S. Laplace, Ernest, A.M., M.D. McCauset, Dr. George H. Marshall, John S., M.D.

Maxfield, George A., D.D.S. Mate, Professor Charles. Mills, William A., D.D.S. Mitchell, W., D.D.S. OsMAN, Dr. J. Allen. Ottolengui, B. a. B., M.D.8. Peck, Bdward S., A.M., M.D. Beed, Dr. J. J. Rehfuss, W. L., D.D.S. BoBERTS, Dr. W. L. Sachs, Wilhelm, D.D.S. Smith, C. Stoddard, D.D.S. Symington, Johnson, M.D.,

F.B.S.£!i. Waitt, J. B., D.M.D. Warren, Dr. George W. Whitefield, George, M.D.,

D.D.S. Wight, J. S., M.D. Wilson, George A., D.D.S. Winkler, George H., M.D.,

D.D.S. Wright, B. P., D.D.S.


Internatioil^ml Journal.

Vol. XI. January, 1890. No. 1.

Original Communicatioiis/



Gentlemen, ^All that lives must die ; and dying, disintegrate and resolve itself into elements that enter into new cycles of use- fulness. This phenomenon of universal disintegration must have aroused the interest of the human intellect from the first moment that it reached such a state of perfection as led it to inquire into the causes of things. If this disintegration did not exist, the matter of organized beings would encumber the earth, and the law of perpetuity of life would be compromised. A great phenomenon presides over this work ; this phenomenon is fermentation.

Our forefathers may have been savages ; but they were clever and observant ones. After organizing their own rude arts, they turned beasts into servants ; they founded agriculture ; planted the grape. This fruit was surely antediluvian, for we are told that Noah, on leaving the ark, planted a vineyard, drank of the wine,

^ The editor and publishers are not responsible for the views of authors of papers published in this department, nor for any claim to novelty, or otherwise, that may be made by them. No papers will be received for this department that have appeared in any other journal published in this country. The jour- nal is issued promptly on the 15th of the month.

* Bead before the Odontological Society of Pennsylvania, at its regular meetings November 2, 1889.

1 1

2 Original Communications.

and experienced its consequepces. Bat though wine and beer are as old as history, it was not until within the last few decades that anything positive has been known as to the true mode of their for- mation. Our knowledge in the matter has been almost identical with our knowledge of medicine, ^that is empyrical. By this is meant that we had observed the facts, aside from the principles which produce them, and which are essential for a true understand- ing of them. In a word, when light dawned upon the true secret of the manufacture of beer, by the immortal discoveries of Pasteur, that same beam spread itself over the whole realm of medicine ; was the light of regeneration to the noblest of sciences.

The brewer learned from long experience the conditions, not the reasons, of success. Often, however, the brewer's beer has fallen into rottenness without any accountable cause. It is the hidden enemies against which the physician, like the brewer, has had to contend that recent researches are dragging into the light of day, thus preparing the way for their final extermination.

While still a young man, Pasteur, who was then a professor of chemistry in the £cole Kormale, of Paris, was attracted by a note of the Grerman chemist Mitscherlich, in which he said to the Academy of Sciences : ^' The tartrate and paratartrate of soda and ammonia have the same chemical composition, the same crystalline form and angles, the same specific weight, and the same double refraction. Dissolved in water, the refraction is the same. But the dissolved tartrate turns the ray of polarized light to the left, whereas the paratartrate is indifferent But," adds Mitscherlich, *Hhe nature and the number of the atoms is identically the same.*' Pasteur, who was then but twenty-five years of age, discovered that the crystals which turned polarized light were not symmetrical. He noticed that all products of organic life were dissymmetrical, such as starch, quinine, strychnia, etc., while all mineral crystals, or products of the inorganic world, were symmetrical. He immedi- ately suspected that tartrates were organic, that is, connected di- rectly or indirectly with life. It was a well-known fact that a Ger- man manufacturer of chemical products having thrown away some impure tartrate of lime, mixed with albuminoid materials, this had fermented, giving rise to different products. Pasteur reproduced the fermentation in the following way : Taking some tartaric acid, he added a certain amount of albuminous material, and placed it in an incubator. When fermentation had taken place, Pasteur found in- numerable small living organisms; and after the process had stopped he polarized the liquid, and found that, whereas before fermenta-

Fermentation : its Cause and Effects, Laplace, 3

tion the polarization was to the left, it had now turned to the right.

His suspicion was realized.

Hence, this sudden change of the direction of the ray of polar- ized light was accompanied by a great development of small living organisms during a process heretofore known simply as fermentation. This was the first hint ever gotten of the influence of a living micro- organism upon organic substances. This micro-organism was not present apparently when the mixture was placed in the incubator, and now it existed in swarms in the disintegrating mixture. They surely grew during the fermentation.

Up to this time the most incomplete notions had been entertained as to the true cause of fermentation. Liehig said " it was an acidi- fication of albuminous substances when in contact with air;" Gay- Lussac thought that the oxygen of the air was the causative agent, for he had noticed that wine had turned sour from being poured from one vessel into another; Berzelius and.Mitscherlich said that ferments acted by catalysis, that is, by their presence ; Schwann and Cagnard Latour noticed that a living rounded body was pres- ent in the manufacture of beer, but it did not occur to them to ascertain what part was played by this organism. As soon as the malt is mixed with hops it is boiled and allowed to cool ; this in- fusion is called the wort, and that is placed in vessels with but one aperture open to the air. Here it is mixed with the yeast. Soon after a brown froth forms on the surface, which is really new yeast, and issues from the aperture falling like a cataract into troughs prepared to receive it. Whence is this new yeast ? Weigh it before and after. The brewer sows ten pounds and he collects fifty pounds. Shall we say that this is spontaneous ? Are we not reminded of the seed that has fallen in good soil and brought forth fruit fifty- or a hundred-fold ? In fact, this seed can be seen budding under the microscope before our own eyes. It is a minute plant, the torula cerevisisB. This marks a distinct epoch in the history of fermentation. But Liebig was loath to accept the growth of this plant as the cause of fermen- tation, and maintained that its life had nothing to do with the pro- cess, that it was a purely chemical one, and that it was the chemi- cal nature of yeast, not the fact that it was alive and could develop life, which produced fermentation. In a memorable demonstration, Ludersdorf proved the error of Liebig's assertion, and that yeast acted as a ferment because of its organized or living character. He destroyed the cells of yeast by rubbing them on a ground glass plate, and he found that, with the destruction of the organism, the

4 Original Communications,

chemical nature remaining the same, the power to act as a ferment disappeared totally. No experiment could possibly be more con- clusive.

But in the manufacture of wine no yeast is added. The grape is pressed, and the juice ferments after a short while. The torula soon make their appearance, however, and where do they come from ? If the filtered grape-juice be boiled, so as to destroy the germs it contains, and be put in germless air, it will never ferment. All the material for spontaneous generation is there, but the life both in the grape-juice and the air being destroyed, no new life can be produced in the shape of fermentation.

Pasteur has pushed this demonstration still further. The grape is sealed by its own skin from contamination by the air. He con- trived a way of extracting the juice without its touching any con- taminated substance and placing it in pure air ; it did not ferment ; then taking the skin of the grape and brushing the delicate grayish dust upon this non-fermenting juice, fermentation soon developed, and the yeast-plant appeared in great abundance ; proving that the grape carries its yeast upon its own self For thousands of years, therefore, the wine-grower has done unconsciously what the brewer does purposely.

The germ of the yeast-plant exists in the air, but not in quanti- ties suflScient to insure rapid fermentation, such as the brewer de- sires, hence the brewer puts in a quantity himself Pasteur has defined fermentation as life without air. These germs live on oxy- gen, as we do, and give off carbonic acid gas ; but they do not take their oxygen from the air, they take it from the substance upon which they grow ; hence they do not need the oxygen of the air for their development. Hence fermenting substances are placed in vessels with but a small aperture to the open air, where the yeast imbibes oxygen and pours forth carbonic acid. Where does it get the oxygen ? It is wrenched from the liquid upon which it grows ; liberates carbonic acid gas, and leaves the liquid product as our familiar alcohol.

And in the same way exposing alcohol to the action of the fer- ment known as the mycoderma aceti, acetic acid will be the result.

The air is full of germs of ferments differing from the alcoholic leaven. Expose milk to the air, and coagulation will take place; small globules of butter appear, the butyric acid fermentation. Within a short while larger organisms are seen wriggling in swarms through the preparation. In curdled milk are found other organ- isms linked together, as beads on a string, that is the lactic acid

Fermentation : its Cause and Effects, Laplace. 6

fermentation. Examine putrefying milk, and it will be seen to swarm with millions of small and larger germs, showing wonderful alacrity of motion. Keep your milk from the influence of the at- mosphere, or boil it so as to kill the germs within it, and it will remain sweet, the germs being destroyed. Expose meat to the atmosphere, and it will soon putrefy ; it will swarm with the germs of putrefaction, and will soon stink. Keep the germs away, and it will not putrefy. Thus we begin to see that within the world of life, to which we ourselves belong, there is another world requiring the microscope for its discernment, but which, nevertheless, has a most important bearing upon our welfare.

Gathering these facts together, and analyzing them, we see that there are two elements always in action, a seed and a soil: the seeds are floating continually in the atmosphere about us; the soil is the particular substance upon which these germs fall, and at the expense of which they grow. It follows also that the greatest analogy exists between these various germs in the atmosphere and the seeds of various planto that may be wafted by the wind from one spot to another, and which develop when they happen to fall upon a suited soil.

Another fact is that, just as when you sow corn, corn is reaped and not barley, so each particular germ grows its particular kind. Supposing you take a handful of seeds of various flowers, and sow them in the same soil, then the different plants will grow alongside of one another. So also, if various sorts of germs have access to the same soil, they may grow plentifully together, as takes place in putrefaction, where germs of many kinds are seen growing and de- composing the soil upon which they grow, liberating not carbonic acid, as in fermentation, but sulphuretted hydrogen, the foul smell of putrefaction.

All germs will not grow on the same soil, just as all seeds will not grow in the same ground ; some plants being indigenous to some countries and others to different climates. But a very astonishing fact is that one germ, after developing in a particular soil, may leave that soil in such a state as will render it favorable to the develop- ment of a germ which could not have developed there before. Such is indeed the case with the mycoderma aceti, which could not have developed in the sweet solution. First, the yeast-plant developed there, changing the sugar into alcohol, and now the mycoderma aceti, falling into the alcohol, grows abundantly, changing this alcohol into acetic acid or vinegar.

The most important and practical portion of the whole knowl-

6 Original Communications.

edge of the nature and development of micro-organisms is the study of the changes incident to their growth in the soil upon which they develop. The yeast-plant left the sugar changed into alcohol, whose chemical nature* and physiological effects are quite different from sugar. The mycoderma aceti has changed the alcohol into vinegar, whose chemical nature and physiological effects are vastly different from alcohol. Likewise the lactic acid germ has produced in milk, which was once sweet, a substance (lactic acid) having corrosive properties, and which curdles the milk.

This new product, which results from the decomposition incident to the development of a germ, is called in medicine a ptomaine. When germs are absorbed from the atmosphere and produce certain diseases, the albuminoids are decomposed within us, and this pto- maine or fermentative product is the chemical poison formed, which, being resorbed by the economy, produces those physiological symp- toms characteristic of a disease.

And would a substance putrefy without the action of germs ? In other words, is there such a thing as spontaneous generation ? TyndaU's and Pasteur's admirable researches have set this question at rest. One will suffice. Having made veal broth, Pasteur placed it in a round vessel, with but a small aperture. This was raised to a temperature of 115^ C. for half an hour, so as to destroy all the germs within it, and the tip end of the flask was soldered, so as to prevent further air from coming in contact with the broth. A num- ber of flasks so treated were placed aside. I have one in my pos- session thus prepared, many years ago, by Pasteur himself, and its contents are as pure as on the day of its preparation. This shows conclusively that by heat he had sterilized the liquid and interior of the flask, and, having soldered the end of the flask, thus prevent- ing any germs of the atmosphere from having access to the fluid, there was no possibility of life developing in it ; hence it remains pure, and is likely to remain pure indefinitely.

Now, this simple experiment was a master stroke of genius, for on it is founded our whole system of modern pathology and hygiene.

Do we wish to stop fermentation, putrefaction, contagious and epidemic diseases, we must repeat Pasteur's experiment, sterilize first; then prevent the germs from having further access to the parts thus purified.

Strange to say, this process of purification was applied to the canning of goods before it was practically applied to scientific pur- poses. In fact, canned fruits of all sorts are prepared exactly after the manner of Pasteur's broth experiment. They are raised to a

Fermentation : its Cause and Effects. Laplace. 7

high temperature and kept in air-tight vessels. And what occurs when canned goods become spoiled? Simply, the germs of the air have gotten into the goods, either through some small aperture in the vessel or sufficient heat was not applied at first to destroy them.

Lister, in England, was the first to make a practical application of this to suppuration in wounds. He saw the analogy between the foul smell of a suppurating wound and the process of putrefaction, and concluded that, should he succeed in destroying the germs which had started this putrefying process, and should he prevent further germs from having access to the wound, this putrefaction would cease and the wound heal kindly without suppuration. This he did by sterilizsing the wound. There are two ways of sterilizing : (1) by heat ; (2) by chemical agents : carbolic acid, sublimate, etc., which have the property of destroying the vitality of most micro- organisms ; and when, used in proper strength, do so without im- pairing the tissues with which they come in contact. The wound is then covered with several layers of cotton that has been sterilized or purified by heat, and this prevents the germs of the air fVom having further access to the wound ; for as these germs fall upon the outer layers of the cotton, they are caught by the meshes of the small cotton fibres and are not allowed to get any nearer the wound; during this time the normal and unimpeded process of repair goes on, and healing takes place without suppuration or putrefaction produced by germs. And by this glorious discovery Lister has blessed humanity with a reduction in mortality from major surgical operations; a mortality reduced from fifty per cent, before the days of antisepsis to two or three per cent, at the present day in the best-conducted hospitals. Besides, it has widened the domain of surgery, bringing to the surgeon success in such oper- ations, in which he could not hope for success should suppuration take place.

Applying these same principles to dental surgery which is a special branch of general surgery, we are struck by the frequency of processes of putrefaction or fermentation in the mouth. And why ? Because the germs of the atmosphere, which we constantly breathe through the mouth, lodge upon some remnant of food buried in the sulci, fissures, and proximal surfaces of the teeth, and find there a suited soil, accompanied by heat and moisture ; these germs develop and cause putrefaction, as evidenced by the foul odors from the mouth. Besides putrefactive processes, a fermentative process also may take place in the presence of sugar which produces a cor-

8 Original Communications,


rosive element that destroys the enamel. The germs sink into this impaired spot, and the same deleterious agent being generated there, the process of decay attacks the dentine, the pulp, and an extensive cavity follows. Such being the case for a healthy tooth, well paved with enamel, the process is a much easier and more rapid one when through some accident a mechanical abrasion already exists.

To the honor and credit of Professor W. D. Miller, of Berlin, be it said that he was the first to discover that the corrosive substance BO deleterious to enamel, and which results from fermentation in the mouth, was lactic acid, which enters into composition with the cal- cium salts of the tooth, producing a lactate of lime.

This being the case, as a student of pathology and practitioner in surgery, I conjure you to apply to your special branch of surgery the principles of antisepsis that Lister has applied to general surgery, vouching that you will meet the same grand success. To reach this end, sterilize, and prevent the further access of germs to the parts. Sterilize with the acid sublimate solution, destroying the organisms at one sitting. But when the pulp is dead use the heated platinum broach in the root-canals, then use the antiseptic solution, which will penetrate the minute nooks of the cavity, and destroy those few germs that have perhaps escaped the heat ; finally, plug the tooth with aseptic or antiseptic filling. And, gentlemen, as a physician, knowing how many general disorders, gastric and others, are caused by germs that found originally a brooding-place in the mouth, I im- plore you to give this question of oral disinfection your most scru- pulous attention, feeling confident that a rational and persistent use of the antiseptic solutions now within our reach will afford you the fbllest satisfaction, for in your treatment you will meet the same glorious success as is achieved in surgery as practised at your doors.

And now, having reviewed the various phenomena of fermenta- tion, we see that in the eternal laws of the universe fermentation was destined as a power for good, and, like electricity and steam, it vastly benefits our existence, if only rightly understood and maintained within its proper bounds; that most of the harm to humanity resulting from fermentative processes is due to our still incomplete mastery of its laws ; and that with the present strides of science, we will completely overcome those micro-organisms or fer- mentative agents that are deleterious to man and his surround- ings.

Such is the triumph of the scientific age in which we live, that has disclosed a world about us which we knew not of; a world of

The Waste Prodricts of the Body. Mayr. 9

beings consisting of enemies as well as benefactors, in constant and

intimate relation with each of us.

We know of numberless stars above, infinitely large, but this

newly^iscovered world of infinitely small beings, its laws and pur-

poses, is to me not a lesser index to that Power, the Author of them


<* That Qod which ever lives and loves, One God, one law, one element, And one far off divine event To which the whole creation moves/'



The chief instruments supposed to be used in a dental office are excavators, pluggers, and forceps, to which may be added vul- canizers, and such appliances ; but the chemical " tools" have also been multiplying of late too. The various antiseptics have come in use more and more ; ansesthetics and disinfectants, which con- stitute a large proportion of the materia medica of dentists' use at present, are what might be called of a defensive nature. Very little of it is positive ; that is, almost all medicines used are aimed at the destruction of some enemy, not at the strengthening of the re- sisting body in the struggle for life which goes on and in every cell, every aggregation of cells, every tooth, every individual, every col- lection of individuals, every thought, and every train of thoughts, every system of philosophy or creed. This struggle for life can be essentially reduced to two contending bodies, the one the aggres- sor, and the other the defendant. As in warfare, between the large collection of cells called man the survival of one party is determined by its own strength or by the weakness of the other party. We have in history very many illustrations where a nation has been victorious in its struggle against another nation by its superior strength. Of course one has to be the weaker, but both may be above the average in strength, and yet the still more vigorous party will be victorious. We all want to be conquerors, none of us want

^liead before the New Jersey State Dental Society, at its nineteenth annual session, at Asbury Park, July 19, 1889.

10 Original Communications,

to be beaten and crowded out ; for nature has only one penalty for being beaten, and that is death. The conqueror Booner or later must die. The conquered old Greeks and Bomans are dead. Cer- tain elements among them which were stronger than those of the conquering barbarians have survived. A conquest does not always mean a conquest in every particular. The Goths, in the third, fourth, and fifth centuries, conquered the whole of Spain. They conquered the men, but they did not conquer the women. The Spanish women taught the children of the Goths their unconquered language, and thus the conqueror was vanquished on the field in which he was weak. The Spanish woman and her language utterly annihilated the Goths. There are not a hundred words in the Spanish language to-day which testify to the possession of that country by the Germanic invaders for three hundred years, and, if we did not know the events from history, no linguist would ever suspect such a long and thorough dominion.

The same principle applies to every single cell in the individual man. Every man commands an army of thousands of millions of soldiers. The enemy is just as numerous. Each cell has its enemy, each aggregate of cells has an aggregate of cells as an enemy, and the aggregate man himself has another aggregate man as an enemy. What is the aim of man's existence ? Certain cells of the brain may have different aims, but man, as a whole, wants to live as long as possible and preserve the aggregate of its army intact as long as possible. By two methods he tries to reach this aim : by weak- ening the hosts and groups of enemies, and by strengthening his own army and groups of soldiers. His staff of generals ^that is, his brain must equal those pitted against him. His soldiers that is, his cells must be equal or stronger than those of the enemy. The generals in the brain employ auxiliary troops to strengthen their army. The dentist is one of these auxiliaries. He has studied certain points about the enemy; he has been a spy in their camp. Under the guidance of that Pinkerton of detectives. Dr. Miller, of Berlin, he has traced the enemy into his lair; he has investigated his method of growth and attempted to reach him in a vital spot. Almost all the efforts of dentists have now been directed towards weakening the enemy. What is the use of a weak enemy if it puts a premium on our own weakness ? I think it would be much better to have a strong enemy pitted against our own strength.

To carry out the comparison still further, during our youth we build our fortress on which we have to depend after our growth is finished, until, with an army of crippled, maimed, and exhausted

The Waste Products of the Body. Mayr. 11

veterans, we have to surrender. Our lungs lose daily some of their best cell soldiers. Our heart burns up every day a few of the most active workers. It is, therefore, best to start with as powerful an organization as possible. The special branch of the army which we have to consider in this meeting is that of the masticators, a branch of the sutlery department. Now, many a strong army has been beaten in its sutlery department. They do not have to do any active service ; they have to attend to, perhaps, less heroic wants than the brain or the eyes, but without strong grinders there can- not be a strong army. The building up of strong teeth in children seems to me to be a far more important problem than the extracting of six-year molars. It is true that General Brain has also provided for that emergency. It has hired steam grinders and furnishes the grinding of the sutlery department. It supplies in hash-shape all vegetables, meats, and cereals. Bread and cheese are made with mushy softness. But without strong masticatory organs we will always be conscious of a weak department in our army. The best «and only natural process of growing good teeth in children is to have their parents grow good teeth, of course before the children are bom ; which saying is not quite as ridiculous as it might at first appear, for it may be observed that parents very frequently do things for the good of their children which they ought to have done before the children were bom. But the fact remains, in spite of all those probably correct principles, that children are born with weak teeth. What shall we do ? We cannot afford to kill them and grow better ones. For some time it has been the peculiar treat- ment of dentists to give phosphate of lime and phosphate food in general, with the idea of supplying that which was supposed to be wanting, the lime salts in teeth. You can pack such children in a lime-barrel, and their teeth will not take up a particle more. You can feed them lime hash and lime stew without effect. The lime has to be introduced through the proper channels and in proper form. The digestive department of the body is just as full of red tape as that of any government. All its supplies have to go a cer- tain regulated course, without which they are not accepted.

Another group attached to the staff of humanity has made the investigation of leaks in the various departments their specialty. Chemists and physiologists belong to that group. Very often they are not admitted to the interior workings of the various depart- ments, but they examine the refuse and see what is going on. They also examine the refuse of the body and try to make conclusions about the processes inside.

12 Original Communications,

The urine is a most interesting waste product. As a rule, I do not think it has been considered to come within the province of the dentist ; but perhaps I will be able to convince you that it is very important that he should know something about it. Urine contains a certain quantity of solid substances ; the rest is water. The solid matter consists of more than twenty thousand dififorent substances. There is salt, urea, phosphoric acid, lime, potash, soda, magnesia, uric acid, etc.

In order to make a perfect analysis of the urine it is necessary to have a very nice set of chemicals. I have come to certain con- clusions in my work, which those of you who are given to that kind of work may be able to appreciate.

If we take urine voided at different times of the day, it shows variations in its specific gravity, say 1021 in the morning, 1018 at noon, 1029 in the evening, and 1030 before going to bed. That is about the regular course. The amount of urea will show a similar variation. The phosphoric acid will show a corresponding variation, and the salts and uric acid also. There is a law which, strange to say, I have not found laid down in any of the text-books, namely, the relative proportion of those constituents in normal urine is almost a fixed one, regardless of the times.

The most constant relation is that of the urea to the phosphoric acid, which in healthy, normal urine is 100 to 8. If 100 parts of urea are excreted, 8 parts of phosphoric acid have to be excreted. The variation of these constituents in normal urine are from a maximum of 100 to 8} to 100 to 7}. If this relation of urea to phosphoric acid varies any more than that it shows defective nutrition.

I find that the ratio of phosphoric acid excreted is about the same in food. In the body itself the phosphoric acid bears to the nitrogeneous tissue the relation of 10 to 100. If the ratio of free phosphoric acid in the urine is more than 8 to 100, it shows very plainly that the person is living on his body, and not on the food taken. If the ratio is 10 to 100, it is a very dangerous condition. I have found it 11 to 100 during the last days preceding death. If the ratio sinks to 4 to 100, it is a sign that the person is strongly assimilating and gaining in weight. So also does the ratio of urea to phosphoric acid tell us what the state of health of the person is, and is most interesting in that respect.

Dentists have speculated a good deal about the dissolving of phosphates. I have, unfortunately, not been conversant with any specimens from dentists in marked cases to show in what way it

The Waste Products of the Body. Mayr. 13

would have a bearing. I should say that if the ratio of phosphoric acid to urea is 100 to 9, no phosphoric acid could be assimilated in the body; and if the ratio be 100 to 4, phosphoric acid and tissues would be freely retained in the body.

Another important constituent is uric acid. That is found in small crystals, which look like Connecticut red sandstone. This uric acid, when perfectly purified, is colorless. We do not know where it is manufactured ; but we know it bears a close relation to the digestive process. Uric acid in the proportion of 100 to 3} shows a strong digestion ; in the proportion of 100 to 2 it shows a weak digestion ; 100 to 3 is about normal. If you find a high amount of phosphoric acid excreted from the body, with low per cent, of uric acid, the person is feeding on his body. If you observe a low per cent, of phosphoric and uric acid, there is a little wasting away of the tissue, and not very good health.

Another important thing is the sum total of the other constit- uents. Salt occurs in the urine in variable quantities. It depends upon the food taken. After breakfast the quantity excreted is con- siderably higher than after supper. It goes through the body without much change ; therefore, chemically, the ratio of salt is not very important. Of the other constituents there are several thousand in normal urine that bear a strict relation to the unit of urea. Those other constituents ought to be about as 100 to 40-70 ; 100 to 120 indicates the formation in the body of abnormal products. There are, furthermore, coloring matters. These are totally un- known substances that we have not yet isolated. There are organic substances, like creatinine, etc. ; and finally a small quantity of sugar, which is rarely absent. From an examination of the com- parative quantities of these constituents you can form an excellent opinion of the working of the body ; better than by any other investigation.

I think the subject of urinary analysis is worthy the attention of dentists. Suppose we have found, after investigation, that the per cent, of phosphoric acid in the urine is high ; the person is excreting more, in spite of a good digestion, than he ought to; he is consum- ing more of his flesh than he ought to. What can we do? Shall we give him acid phosphates ? Not at all. The acid phosphate is not the phosphoric acid of the body. It is as different from that of the body as it is from sulphuric acid. Therefore the idea of pre- scribing phosphate drinks for the purpose of supplying the deficiency of the phosphates seems to me unreasonable and useless. Bone phosphate, made from the powdered bones of animals, was

14 Original Communications.

given, ID olden times, in the shape of powdered mice, carefully dried, etc. A little bit of that phosphate may possibly be assimi- lated, but I have my doubts whether any perceptible particle can be assimilated. The assimilating apparatus will take only things that are presented in a certain prescribed form; it will receive the mineral elements when presented in combination with albuminous substances, as in bones, plants, flesh tissue, etc., but it will not accept phosphates alone. So I think that in cases of excessive excretion of phosphoric acid it is of no use to try to put more into the body ; it does not do any good. We have to see whether that excessive excretion has not something to do with wrong digestion. As a rule, where there is an excess of phosphoric acid excreted you will find low uric acid, showing that, no matter how much phosphates you put into the body, they are not assimilated. We have to direct our attention to the digestive process. I am not sufficiently conversant with the methods which you use to correct or improve them.

If a child were to be fed exclusively on potatoes, there might be a certain deficiency of phosphates in the body ; and I do not doubt that, to a certain extent, a lack of hardness in the teeth of the child might be ascribed to the defective food.

It has been found that a certain ratio must be preserved between urea and phosphoric acid, in order to keep the proper balance of the economy of the body.

This conclusion, which I have reached by comparison of thou- sands of experiments, seems to me a very valuable one. By ex- amining the urine of a patient whose teeth seem to decay and go rapidly, something valuable might be found, in order to see whether this is owing to a solution of the phosphate substance within the body or to the action of external agencies. This might be of special value in children. Now, perhaps having discovered such a leak, what can we do? We have to examine whether the wastefulness in this department is owing to incompetency or to lack of supply. If the first is the case, as we cannot do away with incompetent in- testines, we must try to make them more competent by either vigor- ously arousing their laziness with what we call tonics or by gently pleasant treatment in the form of rest. The treatment has to be ad- justed to the individual. If, on the other hand, we are well satisfied that there is a deficiency of supply, we have excellent and abundant supplies. Flour of the entire wheat, rye, and oats contain a vast amount of phosphates, and in a form in which they are combined with albuminous substance, and accepted by the red-tape depart- ment of the body. If they are not combined with albuminous sub-

T?ie Waste Products of the Body. Mayr, 16

stances, they are most universally rejected. Another very valu- able indication as to the requirements of this department may be furnished by another product of waste of the body, namely, uric acid. We do not know exactly from what it is produced, nor what part of the body produces it, but a relation between the digestive powers of an individual and the excretion of uric acid certainly exists. Especially in disease of the kidneys the ratio falls very low, while in those of the stomach it goes high. If we there- fore find a deficiency of phosphoric acid excreted with the ratio of uric acid high, we may consider that person as suffering, if he suffers, from too rapid digestive process, a thing just as bad as too slow. If we run a boiler which requires for good working two tons of coal a day with the consumption of four tons, we not only waste money, but we burn out the boiler much quicker. If the excretion of phosphoric acid is normal, while that of uric acid is high, prob- ably only dyspepsia is indicated, that is, irritability of the stom- ach. If phosphoric acid be normal and uric acid low, the person is in danger of having to live on his body at the least disturbance of digestion. If, on the other hand, phosphoric acid is high and uric acid is low, that person is severely sick.