THE ANALYST. 357 RESULTS O F EXPERIMENTS ON T H E EFFECT O F BORAX ADMINISTERED WITH FOOD. BY H. W. WILEY. THE following is an abridged account of Circular No. 15 issued by the United States Department of Agriculture and the circular is itself a digest of a much larger buIletin presented to Congress in accordalzce with an authority from that body conferred on the Secretary of Agriculture to investigate the influence upon health and digestion of various substances added to foods either as preservatives or colouring matters and to establish principles which should be a guide to their use. I t is pointed out that an important; point of distinction between modern preservatives and the long-established ones-salt sugar vinegar and wood-smoke-is that in the small amounts used they are almost without taste or odour and their presence in a food product would not be noticed by the consumer unless specifically proclaimed.In determining che plan of the investigation it was decided for well-considered reasons neither to employ artificial methods of digestion nor to experiment upon the lower animals but to employ the human organism itself. As it was impossible to insure absolute control over a number of experimentees a number of young men employed in the Civil Service were selected. These volunteered for the experiment, and were simply placed upon their honour to obey certain rules and regulations imposed on them whilst the experiments lasted. They were allowed to follow their usual vocations. Applicants who were in the habit of consuming alcohol mere excluded but the moderate use of tobacco was allowed.The hours of meals were fixed as follows Breakfast 8 a.m. luncheon 12 a.m. dinner 5.30 p.m. these being the customary meal-times of those employed in the service. The meats selected were roast beef beefsteak veal pork chicken and turkey fish and oysters; also eggs were served twice a week milk and cream fresh vegetables and fruits of the season, and others preserved by sterilization only. Soups were purchased from a large manufactory. The greatest pains were taken to secure absolute freedom from antiseptics of the whole of the food consumed. Coffee and tea were allowed i 358 THE ANALYST. moderate uniform quantities. Custards rice pudding and ice cream were given at regular times. A liberal supply of fruits was incorporated with the food-supply.The bill of fare was varied every day but recurred regularly in seven-day periods. The dining-room arrangements were made in an inexpensive manner but so contrived as to insure a neat and attractivc table. Three divisions were made of each series of observations-namely fore period preservative period and after period ; the time assigned to each of these varied somewhat and the total time of the three extended from thirty to seventy days. During the entire time of observation the rations of each member of the table were carefully weighed or measured and the excreta collected. The object of the fore period was to determine as nearly as possible the quantity of food required to maintain the body-weight at nearly a constant figure, and to determine the normal metabolism as a basis of comparison with that of the preservative period.Preceding the fore period the quantities of food freely chosen by each individual were noted so that some idea might be formed of the proper amount to be weighed or measured. If it was evident that too much food had been habitually consumed keeping the body in a plethoric state the rations were cut down somewhat in order that this condition might be removed. The quantity of the ration was therefore varied either by increase or decrease until at the end of about ten days there was no very marked daily change in weight. I t was found impracticable, however to secure an absolute constancy of body-weight since climatic conditions, slight differences in the amount of exercise and variations in the quantity of excreta, all combined to produce variations in weight (as ascertained at any given period of the day) which are more or less independent of the actual quantity of food consumed.I n order that these daily variations might be eliminated from considera-tion in the comparison of data the average weight for the fore period was taken as the initial point. The quantity of the ration having been thus determined by the observations of the fore period the preservative period was entered upon. During this time the quantity of ration previously determined was given without variation except in case of sickness or some unavoidable condition and to this ration a certain quantity of the preservative to be studied was added.Borax was selected as the first preservative to be experimented with both because it is probably the most important of the commonly used preservatives and also because it lends itself to purposes of demonstration the most readily. The pre-servative was exhibited in two forms-namely borax and boric acid - as it was thought possible that the soda entering into the former might produce some modifi-cation of the results. During the first part of the experiments here described the borax or boric acid was mixed with the butter. In later periods of the study it was deemed advisable. for reasons given hereafter to administer the preservative in capsules. Preliminary experiments had shown that there was no objection to this method though it is different from the actual method of consuming preservatives when added to foods in the ordinary way.I n the administration of the preservative small quantities were first given approximately as much as would be consumed in eating foods preserved with borax such as butter and meat. These quantities were progressively increased for the purpose of reaching if possible the limit of toleration of the preservativ THE ANALYST. 359 by each individual. For each variation of the quantity given a separate study of the digestive processes as influenced by the preservative was made. At the end of the preservative period the after period began during which practically the same quantities of food were given as in the preservative period, the preservative however being omitted. The object of this after period was to restore the individual as nearly as possible if there had been any disturbance of his physical state to the condition precedent to the beginning of the experimental period.During the entire time from the beginning of the fore period to the end of the after period the foods were weighed or measured and analysed and the excreta collected and analysed. The whole of the persons experimented on were placed under medical super-vision being visited by a medical man twice a week who submitted them to a careful physical examination symptoms of any disturbances in their physical state being inquired into. Those cases where persons were unable to continue their services during a whole period were duly noted in the details of the experimental work. Any changes in the relative number of corpuscles of the blood or in the blood-colouring matter were noted but this was not commenced at the beginning of the experiment and does not cover the whole time of the work.The body-temperature was taken daily sub lingua as also was the rate of the pulse any alteration in these being verified by a second observer in addition to the subject himself. The weights of the body were ascertained by means of a platforni scale with agate bearings and of a delicacy sufficient to register easily differences of weight of 10 grainmes when carrying a man of average weight. The subjects were weighed without clothes and it is not safe to assume that the weight of clothing remains constant. In the general discussion of the influence of weights it mas deemed advisable to take the average weight for a period of days rather than the separate weight for any one day.Aside from the usual difficulties connected with analytical practice which must always be taken into consideration there are some special points in connection with a work of this kind which must be mentioned. These difficulties are connected chiefly with the collection and analysis of the excreta. The principal object in the analysis of the excreta as is evident is to establish the relation between certain ingested elements and those which appear in the excreta. Certain forms of food are more or less completely changed in passing through the body and are oxidized and manifested as heat and energy. The fats and carbohydrates are types of food of this kind.Certain other elements in foods. while they undergo marked changes of combination during digestion assimilation and excretion appear in the excreta in practically the same quantity in which they are found in the food. Among these substances may be particularly mentioned nitrogen sulphur and phosphorus. In a state of equilibrium where the body is exercising all of its functions in a normal manner and where there is neither increase nor decrease in body-weight, the quantities of nitrogen sulphur and phosphorus which are excreted should be the same as those which are ingested in the food. This should not be construed to * 360 THE ANALYST. imply that the actual elements eaten on one day appear in the excreta of the next day. Were it practicable in experiments such as these to collect absolutely every particle of emergent nitrogen for instance the balance between the entering and departing nitrogen should be complete.In these experiments however no attempt was made to collect any of the nitrogen except that removed from the body in the urine and faxes. This of course represents nearly all of the nitrogen excreted but not quite all. The same statement may be made with reference to the sulphur and phosphorus. I t is evident however that if a relation can be established between the total amount of these substances entering the food and that leaving the body in the urine and faxes any disturbance of that relation by the addition of an abnormal con-stituent to the food such as a preservative can be easily detected.Therefore for the purposes of these investigations the fact that complete collection of these elements from the body is not secured is not a valid objection to the deductions which are made from the data. Nevertheless it should be pointed out with clearness and frankness that in the conditions in which these experiments were made there are possibilities of error which must not be overlooked. Carelessness on the part of the observer himself in the collection of the excreta a violation of the pledge in regard to the conduct of life or an error in analysis would each tend to render the results of less value. That such errors have been wholly excluded from the data submitted is not likely. On the other hand errors of this kind which may have been introduced could not have been purposely made in order to modify the final results of the investigation.Hence it is fair to assume that such errors are to a certain extent compensatory and that they do not affect seriously the conclusions based upon the data as a whole. Those who have worked in investigations of this kind however will understand the great difficulties which attend them as well as the care which has to be exercised in their conduct and will be the more ready to excuse any unavoidable error which may have crept in either in the conduct of the work or the morale of those who were subjected to the experiment. Another important factor which must be considered in the interpretation of the data which have been obtained in these experiments is the effect of regular habits of living uniform quantity of diet and general control of the appetite upon the physical well-being of the subject.I t is usually considered by physiologists and physicians that regular habits of life conduce to health and strength. This theory has been corroborated by the results of the experimental work here detailed. While it is true that in many instances during the progress of the investigation the experimentees were made temporarily ill by the quantities of the preservatives administered it is nevertheless, an interesting fact to note that at the end of the year after the final after period had been passed they appeared to be and declared themselves to be in better physical condition than when they entered upon the experimental work seven months before.This fact as has already been stated must not be neglected since it is evident that the tendency toward a good physical state and good health produced by the This is far from being the case THE ANALYST. 361 regular habits of life might counteract the unfavourable tendency of any exhibited preservative so that at the end of the observation if the results were judged only by the condition of the subject at that time they might be pronounced negative or even helpful whereas in point of fact the preservative might have produced injurious effects. Self-restraint temperance regularity of exercise regularity in hours of sleep and hours of work are believed to have favourable effects and these were manifested in a marked degree throughout the whole of the experimental work.That the personal attitude of the individual experimented upon influences to a certain degree the progress of digestion is undoubtedly true. Every physician and physiologist is familiar with the marked effect which mental states produce upon the bodily functions. Cheerful surroundings good company and in general an agreeable environment tend to promote the favourable progress of digestion; a reversal of the conditions of environment have exactly the opposite effect. The question therefore arose in connection with the experimental work as to the advisability and possibility of preventing the mental attitude from producing any effect. A careful consideration of all the conditions of the problem made it clear that it would be impossible to conduct the experiments in any way which would exclude from the knowledge of the participant the fact that preservatives were added to the food.I t was fully understood that he was employed for this purpose and the very moment that the observation began upon his daily life by weighing the food and collecting the excrete he would be aware of the fact that he was under observation, and was probably partaking of preservatives. The question also arose whether or not the preservatives should be given in capsules openly or whether they should be concealed in the food itself. Both of these methods received a thorough experimental trial. When the preservative was mixed with the food in such a way as to conceal its physical appearance a certain dislike of the food in which it was supposed to be was manifested by some of the members of the table.Those who thought the preservative was concealed in the butter were disposed to find the butter unpalatable and the same was true with those who thought it might be in the milk or the coffee. When on the other hand, the preservative was given in the capsules with the full knowledge of the subject much less disturbance was created. In fact after a day or two when the subject hecame used to the fact that he was taking a preservative it was apparent that the efYect of the mental attitude was not at all noticeable. All the foods offered were relished because they were known to contain no preservative while the preservative itself exhibited in the form of a capsule imparted no bad taste or other disagreeable effect.If an experiment of this kind were to be continued only a few days it is evident that the mental attitude of the subject would be a matter of much concern; but when from thirty to seventy days are employed in one series of observations and especially when the observations are continued for many months this effect rapidly wears away, and probably does not influence the final results in any appreciable manner. The young men were cautioned to avoid discussing the development of any symptoms which they might notice among themselves and were urged not to dwell These effects may be either favourable or unfavourable 362 THE ANALYST. upon any indications of abnormal conditions which they might experience but to keep their minds employed on their usual vocations and to avoid thinking as much as possible about the experiments which they were undergoing.I n most cases this course of procedure had its desired effect ; and from the general deportment of those upon whom the experiments were made it may be stated with a considerable degree of confidence that the mental state as a whole had very little influence upon the course and progress of digestion. The great difficulties of correctly studying the extensive data which these experiments have given and drawing therefrom the proper conclusions are fully realized. The utmost care must be exercised in these cases to remove all possible personal bias and to free one’s self in so far as possible from the weight of authorities which have been consulted. Public opinion also must not be forgotten in this respect especially when it is considered that it is almost universally believed by the great majority of people that added preservatives are always injurious and in many instances poisonous.But even when personal bias weight of authority and public opinion are eliminated from the problem it is still a most difficult one. So many elements enter into its study so many conditions difficult to control so many idiosyncrasies are to be reckoned with so many external causes influencing health are beyond control that it is difficult in many cases to decide where variations are noticed as to the exact or even the apparent cause which has produced them. The problem therefore has been attacked with a full knowledge of its dieculty and with the desire to be conservative and free from dogmatism.I t would probably be better if all the detailed data which have been secured could be printed in con-nection with this discussion so that the critical reader might be able in every instance to refer to the original figures. Enormous space however would be occupied by the data; and the fact that in most cases they would be of little use in detail has led to the decision to publish only summaries with such detail as may be necessary to point out the way in which the general data have been obtained. If as may appear later on all points of the problem have not been elucidated the failure has not arisen either from lack of desire or froin want of industry in the conduct of the experiment. It is to be attributed rather to the limitations placed upon the observers either by lack of experience or by lack of knowledge how to properly classify digest and study the data at their disposition.A serious attempt has been made to present these data in their full significance and in no case has any tampering therewith been counselled, desired or permitted. The unfortunate fact that many of the data are contradictory must be accepted without question. As the judge and the jury in the light of contradictory evidence seek to decide which is the more trustworthy so have the data herein contained been interpreted with a view if possible to give the greater weight to those which deserve the greater credit. Of interest in connection with the other purposes of this investigation is a study of the relation of the weight of food consumed to the body-weight which was made in detail during the first series of observations.This study was made of each individual article of diet and included a statement of the ratio of the weight of food, including the water consumed and the ratio of the weight of the dry matter in the food to the body-weight. During the fore period first series of observations th THE ANALYST. 363 average daily weight of the moist food including water drunk was 4.20 per cent. of the total weight of the body; during the preservative period 44.22 per cent. and for the after period 4.21 per cent. That is in about twenty-four days the average healthy young man would consume a quantity of moist food including water drunk, equal to his own weight. I t is seen by the above that the administration of the preservative caused very little variation in the weight of food consumed compared with the weight of the body.Reduced to water-free basis the quantity of food consumed in relation to the weight of the body is as follows : Per cent. Fore period . . . . 0.96 Preservation period . . . 0.99 After period . . . . . . 1.01 These data show that there is very little difference between the total quantity of dry matter in the food during the three periods. The total quantity of dry matter in the food consumed daily is in round numbers 1 per cent. of the weight of the body. For a man weighing 150 pounds therefore the quantity of dry matter daily consumed in the food is about 1.5 pounds. I t is also interesting to note that the daily ratio of the moist food including the water drunk is a little more than four times as great as that of the dry food.Similar data for the other series of observations are recorded but the further discussion of the problem is not deemed necessary. I n every series there was a marked tendency on the part of boric acid and borax to diminish slightly the weight of the body although this tendency was in some instances checked during the after periods and a portion of the loss of weight was regained. I n general however there was a tendency to continue the loss of weight during the after periods. The borax and boric acid taken into the stomach during the progress of these experiments were excreted almost entirely by the kidneys. In the first series of experiments 83.05 per cent.were thus excreted in the second series 82.85 per cent., in the third series 63-87 per cent. in the fourth series 82.96 per cent. and in the fifth series 75-17 per cent. During the course of observation 607.4 granimes of preservative were given either in the form of boric acid or the equivalent in borax, of which 468-69 grammes were excreted in the urine or 77.16 per cent. of the whole. These numbers include the data for Series III. where the quantity of the preserva-tive recovered in the urine appears to be abnormally low. I n round numbers it may be said that 80 per cent. of the boric acid and borax taken into the system in foods is excreted in the urine. I t is probable that the rest is chiefly excreted with the perspiration. A careful study of the effect of the preservative administered upon the composi-tion of the faeces shows a slight tendency to increase the amount of water therein.There is however no tendency of any marked nature even when the preservatives are given in large quantities to excite diarrhea. The administration of the pre-servative produces a slight increase in the weight of dry matter in the faeces. Only small quantities are found in the faeces 864 THE ANALYST. There is only a slight effect produced as a whole as determined by the data of experiment upon the excretion of nitrogen. The individual variations are somewhat marked showing the danger of depending too positively upon data from only one or two persons. A slight tendency is shown however on the part of the preservative to decrease the excretion of nitrogen which tendency becomes more marked after the withdrawal of the preservatives.For instance the average nitrogen balance of the four series of observation (excluding Series 11.) during the fore periods is 1.009, during the preservative periods 1.12 and during the after periods 1.74 grammes per day. Expressed as a percentage the combined data show an excretion of 94.2 per cent. of nitrogen taken in the food during the fore periods 93.6 per cent. in the preservative periods and 90-1 in the after periods. The general sumniary of all the experiments with borax and boric acid indicates the largest elimination of nitrogen in the fore periods an intermediate amount in the preservative periods and the smallest elimination in the after periods.This relation is either produced by causes other than the administration of the preservative or the effect of the pfeservative continues after its administration has ceased and even after the preservative itself has ceased to be excreted from the body. It is not impossible that such an influence may be exerted. The retarding influence of the preservative probably increases with the length of the experiment especially in those cases in which the amount of preservative administered is progressively increased. When the administration of the preservative is discontinued the elimina-tion of nitrogen is probably at the lowest point (if depressed by the preservative), and yet during the first days of the after period (at least while the preservative is still in the system) the amount of nitrogen eliminated is probably as low as on the preceding days.There may be a tendency of the preservative in the large amounts in which it is administered to increase the formation of difficultly soluble compounds of nitrogen and by that means if no other retard its elimination from the body. A study of the data relative to the influence of boric acid and borax upon the metabolism of phosphorus reveals many contradictory results. When however all the data are collected into one expression it is found that the influence of these bodies added to the food is distinctly marked on the metabolism of phosphorus and phos-phoric acid. There is a distinct tendency shown by them to increase the quantity of phosphoric acid excreted during the period of the administration of the preservative.In the combined data of Series I. III. IT. and V. the average percentage of phos-phoric acid taken in the food eliminated during the fore periods of observations is 97.3 during the preservative periods 103-1 per cent. and during the after periods 97-0 per cent. The influence of boric acid and borax upon the metabolism of fat is not very marked. There is a slight tendency shown to decrease the elimination of fat in the faxes during the administration of the preservative and a tendency to recover is shown during the after periods. The percentage of fat ingested in the food eliminated during the fore periods is 4.1 during the preservative period 4.0 per cent. and during the after periods 4.2 per cent. These data show that almost no disturbance in the metabolism of fat is caused by the administration of the preservative.The collected data of all the series (except Series 11.) show that 6.4 per cent. o TAE ANALYST. 365 the combustible matter in the food is eliminated unburned during the fore periods, 6.6 per cent. during the preservative periods and 7.0 per cent. during the after periods. These data show a slight tendency on the part of the preservative to interfere with the combustion of the food in the body and this tendency is continued in even a more marked manner during the after periods. The solids summary for all of the series (except Series 11.) shows that the average quantity of solids in the food during the fore periods is 631.5 grammes during the preservative periods 627.6 grammes and during the after periods 614.1 grammes.The average daily quantity of solids appearing in the faxes in the fore periods is 25% grammes in the preservative periods 28.6 grammes and in the after periods 28.3 grammes. The average quantity appearing in the urine during the fore periods is 64-48 grammes during the preservative periods 59-37 grammes and in the after periods 56.20 grammes. The average balance of total solids during the fore periods is 544.701 grammes during the preservative periods 539.875 grammes and during the after periods 530.123 grammes. These data show a marked tendency on the part of the preservative to increase the total solids excreted in the fteces and to decrease the total solids excreted by the urine. There is a distinct tendency manifested by the preservative to interfere with the processes of digestion and absorption.Inasmuch, however as the total quantity of solids administered in the food varied slightly in the different periods a fairer interpretation is obtained by comparing the percentages of the total solids exhibited in the food eliminated by the fzeces and urine respectively. In this comparison it is found that the total percentage of solids in the food eliminated in the fzces during the fore periods is 4.1 during the preservative periods 4.6 and duirng the after periods 4.6. The percentage of solids in the food eliminated in the urine during the fore periods is 10.2 during the preservative periods 9.5 and during the after periods 9.1. These percentages indicate also very strongly the influence exerted by the preservative mentioned above.I t must be remembered also in this connection that practically 80 per cent. oE the preservative administered is recovered in the urine increasing to that extent the total solids thus eliminated. I n spite of this however there is a marked decrease in the total solids in the urine and a marked increase in the total solids in the faeces. The combined data of the four series (excluding Series 11.) show that the percentage of nitrogen ingested in the food eliminated in the urine during the fore periods is 85.7 during the preservative periods 85.1 and during the after periods 81.1. This shows a tendency on the part of the preservative to diminish the percentage of nitrogen excreted in the urine and this tendency is continued in a very marked manner in the after periods.The data of Series IT. III. and V. show a marked tendency on the part of boric acid to increase the acidity of the urine. In no case during the administration of boric acid was an alkaline reaction observed. I n the case of the urine the marked acidity imparted to it by boric acid is continued in most cases throughout the after periods. The data of Series IV. and V. on the contrary show a marked tendency on the part of borax to diminish the acidity of the urine and in several instances this substance imparted to the urine an alkaline reaction. These facts indicate that a large part of the borax and boric acid administered is excreted unchangedin chemicd composition 366 THE ANALYST.Very little effect is produced by these preservatives upon the volume of urine, although there is a slight tendency manifest to decrease the amount. There is a slight tendency also manifested during the administration of the preservatives to decrease the total solids in the urine. I n this connection however it must be considered that the season of the year has a marked effect upon the amount of urine secreted the tendency being to secrete larger quantities in cold weather than in warm. Combining the data of Series I. III. IV. and V. for those members completing the series we find that the average daily amount of urine secreted during the fore periods per individual is 969 c.c. during the preservative periods 960 c.c. and during the after periods 952 C.C.These data show almost no effect of the preservatives on the quantity of urine secreted but there geems to be a slight tendency to decrease the amount secreted in the preservative and after periods. I n those few cases where there was normally a mere trace of albumin in the urine it is shown by the data that the general tendency of the preservative used is to increase the trace of albumin in the urine and this increase is manifested also during the after periods. Microscopical examinations of the urine were made for the following substances : Uric acid crystals ; urates ; oxalate of lime ; phosphates (a) crystalline phosphates (b) amorphous phosphates ; epithelium cells of all kinds ; leucocytes ; red blood - cells; casts (a) hyaline ( b ) finely granular ( c ) coarsely granular, ( d ) epithelial ( e ) other forms ; mucous cylindroids ; mucous strands.The microscopic examinations were made at three periods during each series, except in Series I. during which time the microscopic supervision of the urine had not been instituted. The examinations were made once during the fore period once or more during the preservative period and once near the close of the after period. Reviewing the data as a whole in regard to the appearance of these microscopical bodies in the urine the facts which appear prominently are the great variations in the number and character of these microchemical bodies. They occur constantly in some cases in very much greater abundance than in others. There are a few cases -in fact quite a number-where the relative abundance of these bodies seems to be increased during the administration of the preservative.There is a smaller number of cases in which the contrary fact occurs. I n the greater number of cases however, the administration of the preservative appears to have had no influence upon the relative abundance of these bodies. The data therefore as a whole cannot be regarded as conclusive respecting the influence of the preservative upon the number or kind of microchemical bodies occurring in the urine, There was no regular influence established relating to the effect of the preservative in increasing or decreasing the number of corpuscles in the blood. The data in individual cases are often contradictory and a general summary of them leads to no conclusive result.CONCLUSIONS. In the consideration of the action of preservatives of a mineral nature such a13 borax and boric acid it must be remembered that mineral substances play a double riile in animal and plant nutrition. First they may serve as real foods necessary t THE ANALYST. 367 the formation and nutrition of the tissues. In the second place they are necessary to the functional activity of the various organs of the body irrespective of any paxt they may take in direct nutrition. Hence the introduction of saline bodies which may or may not be of an anti-septic character may within certain limits have a favourable influence upon health and digestion. At the same time it should not be forgotten that all excess of such bodies iniposes upon the excretory organs an additional burden which while it might not impair their eEciency even for a number of years might finally produce a condition of exhaustion which would be followed by serious consequences.Especially is this remark true of the kidneys which appear to be a general clearing house for all the surplus of saline matters ingested in the foods. I t is admitted by all who have examined the subject in a critical way even by the users of preservatives that in certain maximum quantities the limit of toleration is reached in each individual and positive injury is done. But it is also well recognised that many if not all of the usual foods when used in large excess produce injurious results. The many cases of disease produced by overeating or by eating improperly-prepared or poorly-cooked foods or by eating at unusual times are illustrations of this fact.Upon this basis and upon the further statement that when used in extremely small quantities the preservatives in question cannot be regarded as harmful is founded the principal argument in favour of the use of the preservatives, aside from the fact that the foods themselves axe kept in a better and more whole-some state. I t is only proper to give to this argument full consideration and not to brush it aside as illogical and irrelevant. I t is evident that any attempt to determine experi-mentally the effect of extremely minute quantities of any preservative even when used continuously would not be likely to lead to any definite result. I n the fore-going data we have illustrations of the fact that even large quantities of the preservative employed-larger by far than would probably ever be found in any food product-do not always act in such a way as to permit of definite interpretation.The claim therefore that the use of such preservatives is justified when the amount is extremely small and when even these small amounts are used only at intervals and not continuously is worthy of careful consideration. An illustration which is pertinent may be taken from the particular preservatives with which the foregoing experiments have been made-namely boric acid and borax. One of the food products to which these preservatives are very commonly added is butter. This statement should not be taken to imply that in butter prepared for domestic use in this country borax is found to any considerable extent.When butter however is to be transported over long distances and necessarily kept a long while the addition of borax is very frequently practised. The dietetic data which have been accumulated in the course of this experiment show that the quantity of butter consumed daily varies from 30 to 70 grammes. Suppose as a maximum we say that the quantity of butter consumed in any one case daily is 100 grammes and that it contains 1 gramme of boric acid or an amount of borax equivalent thereto. The maximum quantity of boric acid used in a day in this case would be 1 gramme. I n point of fact however it would rarely if ever reac 368 THE ANALYST. this amount but even in those cases where butter is eaten freely probably 8 gramme would be about the maximum quantity consumed.Further than this 1 per cent. of boric acid or its equivalent in borax in butter is a very large quantity. Probably as a rule not more than one-half of 1 per cent. is employed. In this case the quantity of boric acid likely to be consumed by any one individual in a day would be reduced to 4 gramme. I n the case of meats preserved by borax although larger quantities are eaten than of butter it is not likely that any larger quantities of borax would be consumed. Thus it appears that those who habitually eat butter and meat preserved with borax might be consuming 4 gramme or a little more of boric acid per day. But preserved meats are not regularly eaten and hence the quantity mentioned is likely to be over-estimated.I t would be unwise to affirm in a case of this kind in the light of the data obtained by the experiments that such a minimum consumption oi borax and especially when not a continuous one would prove deleterious within any reasonable time of observation. The question then arises Does the absence of such proof or the impracticability of obtaining it serve as a justifiable excuse for the use of this preservative ? This question ought not to be decided alone because the principle of the decision must stand not only for boric acid and borax but for every preservative used in foods. I n other words whatever principle is established for judgment as to the use of boric acid in small portions must also be applied to the use of every other preser-vative used in foods.The principle must also be still further extended so that whatever may be established as regards butter or meat must be admitted in respect of every other substance used in food. Hence before admitting the full force of the argument based on minimal quantities the full significance of such an admission must be considered and the practically unlimited extent of its application acknowledged. This leads to the discussion of the fact that in the majority of cases the labour of freeing the system from added preservatives falls principally upon the kidneys. In the method of life in vogue in this country the kidneys are already hard-worked organs. Americans probably eat more freely than the citizens of alniost any other country with the possible exception of England.Large quantities of nitrogenous foods are consumed. In the breaking down of the nitrogenous tissues the kidneys are the chief organs for the excretion of the d6bris. The addition of any further burden therefore no matter how minute is to be deplored. If however the principle be admitted that injurious substances may be used in such small quantities as to be practicallyharmless then we find the way open for loading upon the kidneys many different functions in addition to those which they now discharge. If they may be justly called upon to eliminate the small quantities of boric acid added in food they cannot logically be freed from the necessity of eliminating also minute quantities of salicylic acid saccharin sulphurous acids and sulphites together with the whole list of the remaining preservatives which are eliminated principally through the kidneys.It would be useless to contend that the occasional consumption of small quantities of boric acid in a sausage in butter or in preserved meat would produce even upon delicate stomachs any continuing deleterious effect which could be detected by any of the means at our disposal; but naturally it seems that thi THE ANALYST. 369 admission does not in any way justify the indiscriminate use of this preservative in food products implying as it would the equal right of all other preservatives of a like charact,er to exist in food products without restriction. I t appears therefore that there is no convincing force in the argument for the use of small quantities unless it can be established that there is only a single pre-servative used in foods that this preservative is used in only a few foods that it will be consumed in extremely minute quantities and that the foods in which it is found are consumed at irregular intervals and in small quantities.On the other hand the logical conclusion which seems to follow from the data at our disposal is that boric acid and equivalent amounts of borax in certain quantities should be restricted to those cases where the necessity for them is clearly manifest and where it is demon-strable that other methods of food preservation are not applicable and that without the use of such a preservative the deleterious effects produced by the foods themselves, by reason of decomposition would be far greater than could possibly come from the use of the preservative in minimum quantities.I n these cases it would also follow, apparently as a matter of public information and especially for the protection of the young the sick and the debilitated that each article of food should be plainly labelled and branded in regard to the character and quantity of the preservative employed. The most interesting of the observations which were made during the progress of the experiments was in the study of the direct effect of boric acid and borax when administered in food upon the health and digestion. When boric acid or its equivalent in borax is taken with the food in small quantlities not exceeding Q gramme (79 grains) a day no notable effects are immediately produced. The medical symptoms of the cases in long-continued exhibitions of small doses or in layge doses extending over a shorter period shov in many instances a manifest tendency to diminish the appetite and to produce a feeling of fulness and uneasiness in the stomach which in some cases results in nausea with a very general tendency to produce a sense of fulness in the head which is often manifested as a dull and persistent headache.In addition to the uneasiness produced in the region of the stomach there appear in some instances sharp and well-located pains which, however are not persistent. Although the depression in the weight of the body and some of the other symptoms produced persist in the after periods there is a uniform tendency manifested after the withdrawal of the preservative toward the removal of the unpleasant sensations in the stomach and head above mentioned.The administration of boric acid to the amount of 4 or 5 grammes per day, or borax equivalent thereto continued for some time results in most cases in loss of appetite and inability to perform work of any kind. In many cases the person becomes ill and unfit for duty. Four grammes per day may be regarded then as the limit of exhibition beyond which the normal man may not go. The administration of 3 grammes per day produced the same symptoms in many cases although it appeared that a majority of the men under observation were able to take 3 grammes a day for a somewhat protracted period and still perform their duties. They commonly felt injurious effects from the dose however and it is certain that the normal man could not long continue to receive 3 grammes per day 370 THE ANALYST.I n many cases the same results though less marked follow the administration of borax to the extent of 2 grammes and even of 1 gramme per day although the illness following the administration of borax and boric acid in those proportions may be explained in some cases by other causes chiefly grippe. The administration of borax and boric acid to the extent of 8 grainiiies per day yielded results markedly different from those obtained with larger quantities of the preservatives. This experiment (Series V.) conducted as it was for a period of fifty days was rather a severe test and it appeared that in some instances a somewhat unfavourable result attended its use. On the whole the results show that 4 gramme per day is too much for the normal man to receive regularly. On the other hand, it is evident that the normal man can receive ij gramme per day of boric acid or of borax expressed in terms of boric acid for a limited period of time without much danger of impairment of health. I t is of course not to be denied that both borax and boric acid are recognised as valuable remedies in medicine. There are certain diseases in which these remedies are regularly prescribed both for internal and external use. The value which they possess in these cases does not seem to have any relation to their use in the healthy organism except when properly prescribed as prophylactics. The fact that any remedy is useful in disease does not appear to logically warrant its use at any other time. It appears therefore that both boric acid and borax when continuously administered in small doses for a long period or when given in large quantities for tt short period create disturbances of appetite of digestion and of health