iniinnMnnMiMiiniMiiiMiiiiiitiiiiitiiioiiiiniiniitttiniiiniiMiitiii iiitiiiiiiiii!!i!i!!!i!iitiii!iiiiiiiiiiiiiiiiimitiniimiiiiiiiiiiiiiniitlmi1 iiiitmiiiiiiiiiiiiiiiiiiiiiiiiiiir mfrmrnuiTm UC-NRLF B 3 fiMti LdSS ltllllilllllillillill|||||il L.Siinii Ii ilillliillltllllMiJillllliJillliiniillJIMrl!;;;!'-!! in iliiii iMiiiiiii iiiiiii ' W ff'l If ' ti llillJll THE INFANT THE INFANT NUTRITION AND MANAGEMENT BY ERIC PRITCHARD M.A., M.D. (OxoN.), M.R.C.P. (Lond.) PHYSICIAN TO THE QUEEN's HOSPITAL FOR CHILDREN, PHYSICIAN TO OUT-PATIENTS, CITY OF LONDON HOSPITAL FOR DISEASES OF THE CHEST, VICTORIA PARK, HONORARY PHYSICIAN FOR INFANT CONSULTATIONS, ST. MARYLEBONE GENERAL DISPENSARY, CONSULTING PHYSICIAN TO CHILDREN'S HOME HOSPITAL, BARNET, AND TO THE NURSERY TRAINING SCHOOL, HACKNEY ETC., ETC. 1 \ > J J , :> 1 > J » J LONDON EDWARD ARNOLD 1914 Ail rights reser-ced A s \^ /',-./ PREFACE This little volume is founded on a series of lectures which, from time to time, I have given to students attending at courses held by the Queen's Hospital for Children, the Medical Graduates' College and Polyclinic, the National Association for the Preven- tion of Infant Mortality, and other medical societies. Some of these lectures have already been published in part, or in whole, in medical journals, and for permission to republish I have to thank the editors of The Lancet, The Practitioner , The Medical Press and Record, The Clinical Journal, The American Practitioner, American Medicine, Pediatrics, Archives of Pediatrics, and The British Journal of Children's Diseases. In preparing these lectures in book form, it has been necessary to edit somewhat freely, for the same ideas recur over and over again in different lectures. Even in their revised form I am afraid there is some repetition; this is owing to the fact that I deal more with general principles than with details, and these principles apply, with slight varia- vi PREFACE tions, to a large number of different conditions in connection with which they are here employed. Those who read this little book in the expectation of finding a full description of the methods of feeding infants will be disappointed, for according to the views herein set forth each case must be regarded as an individual problem which is to be solved by the practical application of certain general principles. I believe one of the chief reasons why fixed methods of feeding babies so often fail is because the manner in which any particular baby responds to any particular line of treatment depends more on its past experiences than on any other factor, and each infant has its own past. This work is not intended to take the place of more ambitious textbooks or handbooks on the subject of infant management ; it contains views which, in many cases, are still regarded as un- orthodox and revolutionary. Tradition and authority have, however, so narrowly circum- scribed our methods in the past, and one book has so closely followed on the lines dictated by those which have preceded it, that a little breaking away from precedent, even if it is not in all cases an improvement, may perhaps broaden our ideas. E. P. Harley Street, W., August, 1914. CONTENTS CHAPTER PAGE I. THE ESTABLISHMENT OF LACTATION AND THE MANAGEMENT OF BREAST-FEEDING - - 1 — II. SOME PHYSIOLOGICAL PRINCIPLES CONCERNED IN THE NUTRITION OF INFANTS - - - 41 III. SOME PHYSIOLOGICAL PRINCIPLES CONCERNED IN THE DETERMINATION OF THE QUANTITATIVE FOOD REQUIREMENTS OF INFANTS - - 65 IV. MOTOR FUNCTIONS OF THE DIGESTIVE SYSTEM - 92 V. THE TRAINING OF NERVE CENTRES IN INFANTS - 109 _yi. CONSTIPATION IN INFANTS - - - 132 VII. THE RATIONAL TREATMENT OF SOME COMMON • SYMPTOMS IN INFANTS - - - 151 ^TIII. THE USES OF DRIED MILK IN INFANT FEEDING - 181 IX. THE USES OF PETROLEUM IN THE TREATMENT OF CONSTIPATION AND OTHER DISEASES IN INFANTS ..... 19(3 X. CONVULSIONS IN INFANCY - - -' 212 XI. RICKETS: ITS CAUSE AND TREATMENT - ^ 227 XII. THE TEACHING OF MOTHERCRAFT AND ITS IN- FLUENCE ON INFANT MORTALITY - - 241 INDEX ------ 263 Vll THE INFANT CHAPTER I The Establishment of Lactation and the! -HI Management of Breast-Fesding If one tithe of the human ingenuity, which of recent years has been lavished on the artificial method, had been bestowed on studying improvements in the breast-feeding of infants, I believe that compara- tively few infants would even now, in these so-called degenerate days, be relegated to the bottle. It is most gratifying to me personally, in view of the efforts I have made to extend the educational influences of infant consultations, to reahze that many of the improvements in the natural method of feeding infants which have been introduced of late years, are directly due to the energies of those who are engaged in this particular branch of pre- ventive medicine. In this connection I would more particularly refer to the work of Dr. Ronald Carter^ in Kensington, 1 " Breast-Feeding and the Value of the Test-Feed," The Lancet, September 2, 1911. 1 ?'. ; ' /r r: ;^^".' : THE INFANT of Dr. Jessie G. Duncan^ in Birmingham, of Dr. Ella Webb 2 in Dublin, and of Drs. A. E. Naish and Lucy Naish^ in Sheffield. Unfortunately, at our infant consultations vve gain more experience in the general management of breast-feeding than we acquire of that most impor- tant phase known as the "establishment of lacta- tion," for we are seldom called upon to advise on the care of infants under three weeks of age. The obstetric physician, who has unrivalled oppor- tunities for studying the early phases of lactation, is as a rule too closely concerned with the interests of the mother to pay much regard to those of the infant, or to the practical details connected with the establishment of the milk flow. On the other hand, the children's specialist is seldom consulted until breast-feeding has already proved a failure, or until the infant has been weaned and relegated to the bottle. The consequence is that the study of this important stage of breast-feeding falls between two stools — between the apathy of the obstetrician and the want of opportunity on the part of the children's specialist. 1 Eeport on Infant Mortality in St. George's and St. Stephen's Wards. Birmingham, 1913. Printers: Hudson and Son. ^ " Breast-Feeding of Infants," Medical Press and Cir- cular, July 2, 1913. 3 " Breast-Feeding: Its Management and Mismanage- ment," The Lancet, June 14, 1913, p. 1667. BREAST-FEEDING One of the great difficulties with which those who are interested in the problems of infant mortaUty have to contend is the early and unnecessary wean- ing of quite young infants. Dr. Ella Webb, to whose work in Dublin I have already referred, has pubUshed an analysis of the causes of premature weaning of 200 infants who were brought to her infant consultations. The following is a resume of her results : 1. Insufacient milk 2. Illness of the mother . . 3. Disagreement of milk with infant 4. Sore breasts 5. Mother going out to work 6. Advised by nurse or friend to wean 7. Child refusing breast . . 8. Death of mother 9. Hare-lip 10. Accidental illness of child causing great the mother through watchful nights Total fatigue to Gases. 93 35 22 16 13 8 5 6 1 200 I find that my own experience closely coincides with that of Dr. Webb, except for the fact that I meet with fewer instances of illness in the mother and more cases in which the milk is said to have disagreed with the infant. I should also have to include a larger number of cases in Group 6. Unfortunately Dr. W^ebb does not tell us at what dates these infants were taken ofi: the breast. Speaking from my own experience, I find that of all 4 THE INFANT cases of early weaning no less than 33 per cent, are deprived of the breast during the pnerperium, a proportion which in my opinion can be justified by no possible combination of circumstances. A very large number of infants are weaned during the first three weeks of life owing to the advice of doctors, nurses, and friends, on very slender evidence that the breast itself is at fault. Troubles there often are connected with the estabhshment of the motor and digestive functions of the stomach and bow^el in infants, which may make it appear that the milk is responsible; but exactly the same troubles, only in an aggravated form, may ensue when resort is made to artificial feeding. It is quite impossible to determine at first whether a young mother — and more particularly a primipara — will eventually prove a good nurse or not. I have known many most unpromising cases turn out complete successes after a few wrecks of patient effort. During the puerperal period we must be prepared for accidents in connection with the establishment of lactation; but, because our first efforts are not successful, we are not necessarily justified in re- linquishing all further attempts to keep the infant at the breast. The nervous and glandular mechanisms concerned in the secretion of milk are extremely comphcated, and most of the difficulties which arise in connection with breast-feeding are concerned with setting the BREAST-FEEDING 5 machinery as a whole in motion. I beheve that it is never justifiable to wean an infant during the first three weeks of life simply on the ground that the breast remains dry. I have known many instances in which the breasts have remained re- fractory for three weeks or longer, and then have afforded satisfactory supplies of milk. The follow- ing experience illustrates this point: A primipara was confined at full time in a maternity institution. The infant was perfectly healthy, and was put regularly to the breast for the first three days. On the fourth day as no milk appeared in the breast, the baby was given cow's milk in a bottle, and was permanently weaned on the seventh day. Contrary to instruction, however, the mother secretly put the infant to the breast at night in the hope that the milk might come at a later date, and that the inconveniences of a second pregnancy might thereby be averted. On the fourteenth day the mother left the institution and returned to her home still feeding the infant during the day on the bottle, and giving it the breast at night. When the infant was ten weeks old, the mother brought it to my infant consultations, and gave me the details as already described. On examining the baby, I found it much under weight, and in a very poor condition of nutrition. On further inquiry I elicited the fact that, although the mother put the infant to the breast at night with 6 THE INFANT the object already stated, she was under no delusions that the infant derived any benefit from the pro- ceeding, or that her breast contained any milk. Feeling convinced, however, that the infant would not acquiesce in the conspiracy unless it received some reward for its efforts, I examined the mother's breasts, and found, as I expected, that both con- tained a small quantity of milk. So I straightway ordered a test-feed to be given, and much to the mother's surprise, demonstrated the fact that the baby extracted 3 J ounces of milk. In conse- quence of this discovery, I ordered the infant to con- tinue at the breast, and with the exercise of a little care and encouragement, succeeded in postponing artificial feeding until the end of the seventh month. I have little doubt that a large proportion of the cases which are relegated at an early date to the bottle might be saved from the dangers incidental to this proceeding by the exercise of the same degree of patience as that which was displayed, in a less worthy cause, by this poor woman. The following are the particulars of another case which illustrates the value of patience in bringing about a satisfactory secretion of milk under most unpromising circumstances : A woman was confined of lier first baby on Janu- ary 4, 1907, at a maternity hospital. The infant weighed 7 pounds 10 ounces, and was quite healthy at birth. During the twelve days the mother stayed BREAST-FEEDING 7 at the hospital, the infant was put regularly to the breast, and nothing was noticed amiss with him except that there was obstinate constipation. On January 17 the baby was brought to my infant consultations, chiefly because of this symptom, and also because he was losing weight. On being placed on the scales, he was found to have lost 10 ounces since birth. Owing to the loss of weight, constipa- tion, and oUguria, I thought it was extremely likely that the infant was suffering from inanition. So I ordered a test-feed, and found that the quan- tity of milk which the infant extracted from the breast was only a few teaspoonfuls. I therefore ordered a small quantity of whey and cream to be given to the infant in addition to the breast, hoping that by keeping the infant hungry and allowing him also to apply stimulus to the breast, the latter would ultimately become functionally active. During the following week the infant showed unmistakable signs of improvement in his general condition, but repeated test-feeds proved that this result was not due to any increase in the quantity of the breast-milk. During this week the child recovered 6 ounces of the w^eight he had previously lost. On January 28 the infant was again weighed and found to have gained 8 ounces in weight, although the test-feeds still proved that the breasts were nearly dry. By February 4 there was a further gain in weight, and 8 THE INFANT every indication that the glands were beginning to secrete normally. By February 6 the mother felt " the draught " when the child was put to the breast, and from that time forward it was possible to remit the artificial feedings, and the infant made uninter- rupted progress on the breast. The points of in- terest in this case are — Firstly, that it was practically one month before lactation was fully established, and that during the last fortnight the infant was kept in a good condition of nutrition by very small quantities of artificial food (6 ounces of whey and cream in the twenty-four hours). The second point of interest is that the cause of inanition from which the infant was suffering was not detected in the maternity institute in which the infant was born, although the baby presented all the classical symp- toms of starvation — i.e., constipation, loss of weight, and oliguria. Although I shall again refer to these points in greater detail, I would at the outstart emphasize the fact that the establishment of lactation is dependent on the fulfilment of the following con- ditions: Firstly, the nipple must be stimulated by the sucking of the infant ; secondly, the nerve centres which control the functions of secretion and the vascular supply must be in a condition of adequate excitability; and, thirdly, the blood itself must contain a sufficiency of the raw material out of which the mammary secretion can be elaborated. BREAST-FEEDING 9 On purely hypothetical grounds we should naturally assume that the stimulus afforded by the sucking of the infant itself would be more effective in bringing about the reflex activity of the glands than any other form of excitation; it is, however, satisfactory to know that this theoretical assumption has been substantiated by the practical observations of Dr. Jessie G. Duncan.^ In a series of experiments carried out in Birmingham, Dr. Duncan was able to prove that the amount of milk which the pump was capable of extracting from the breast was in all cases considerably less than that which was obtained by the natural efforts of the infant. Further, we have ample evidence from the ex- periences of the late Pierre Budin^ that the total quantity of milk secreted by a nursing-woman is directly proportional to the intensity of the stimulus applied. A weakling baby, with feeble powers of sucking, extracts only a small quantity of milk, whereas a strong, lusty baby secures as a rule a good meal. In his book. The Nursling, he supplies the protocols of the actual amounts of milk sup- pUed by a number of wet-nurses employed in his clinics. Some of the women acted as foster-mothers to two, three, four, or more infants, and the tables show that the greater the demand the greater was 1 Eeport on Infant MortaHty. Birmingham, 1913. Printers: Hudson and Son. 2 The Nursling, Pierre Budin. English translation, first edition, p. 37. 10 THE INFANT the supply. In certain cases of multiple feeding the total amount of milk supplied to the infants in twenty-four hours was surprisingly large. The intensity of the stimulus afforded by the infant will naturally depend on a variety of con- ditions — for instance, on the strength of the infant, and its degree of hunger; also on the shape of the nipple and the sensibility of its tactile nerve-endings . An appreciation of these facts will necessarily suggest a number of practical expedients to promote the activity of the secretory apparatus. For in- stance, in anticipation of possible difficulties in nursing, the nipples should be drawn out and pre- pared for their duties for some considerable time before the date of the expected confinement. This is particularly desirable in the case of the primipara. The best method of drawing out the nipples is to invert over them the bowl of a long-stemmed clay pipe (churchwarden), and then to induce a vacuum by means of suction applied to the mouthpiece. The patient can easily carry out this devise for herself, and she should be instructed to commence doing so for some weeks before the confinement. The rim of the bowl should be well greased with vaseline in order that it may adhere to the surface of the skin, and enable a good vacuum to be pro- duced. It may here be mentioned that quite prob- ably the chief cause of depressed nipples is a pre- existing mastitis, in some cases caused by the ( BREAST-FEEDING 11 so-called " dispersion " of the milk in new-born infants by massage or other improper treatment. The usual plan of hardening and preparing the nipples by treating them with astringents is not to be recommended, for such applications not only dull the sensibility of the tactile sense, but they also tend at a later date to indurate the tissues and to produce cracks and fissures of the epidermis, especi- ally if the infant is rough in its method of seizing the nipple. The indications are not so much to render the superficial epithelium hard and cornified as to make it thoroughly supple and elastic, and to accustom it to the sort of treatment to which it will be exposed when the infant is put to the breast. The best means of preparing the surface of the nipple is to massage it daily with lanoline or some other emollient. It is further desirable to remove all crusts from the surface of the nipples, for such crusts not only tend to form if there is any oozing of secretion towards the end of pregnancy, but after removal by the lips of the infant they leave the underlying epithelium tender and liable to maceration. All these are small matters, but from the point of view of successful nursing they are not without their importance. It is, of course, need- less to say that at the end of each feeding the nipples should be most carefully cleaned with boracic lotion, which should be applied with cotton- wool, and that they should be subsequently 12 THE INFANT thoroughly dried with lint or some other soft material. In order that the infant may apply adequate stimulation to the nipple, it is necessary that it should itself be actuated by the most potent of all incentives — namely, by hunger and thirst. For this reason the humane instincts of doctor and nurse to relieve the supposed wants of the infants by pota- tions of water or other fluids should be sternly resisted. It not infrequently happens, however, that despite our best endeavours, the infant will not apply the desired stimulus to the breast. Under such conditions we must be prepared to resort to other expedients, and to coax the infant to play its part in the estabhshment of the mammary functions. [ Sometimes the smearing of the nipples with a little glycerine, honey, or even condensed milk, may tempt the infant to apply his lips ; at other times a temporary exchange of babies may effect the desired object. Unfortunately, it is not always possible to find, at the required moment, a baby to perform the function of an artificial pump, and considerations of possible infection with syphilis or other disease may damp our ardour, for no one would willingly accept responsibilities of this kind unless the need is commensurate with the risks. In maternity wards, however, there is usually one infant at least which can safely be employed for this purpose, and by employing one in this way a double BREAST-FEEDING 13 purpose is served — the dry breasts of the woman who cannot nurse are stimulated into activity, and the weakly baby can be nourished into life by being placed at the active breast of the other mother. Dr. H. C. Cameron^ describes an interesting case in which such a substitution was effected wdth the most happy results. The accompanying chart Woz. APR. MAY J mi TO (N O CO — CO lO c^ Oi Z ^ 52 f lo O ^ o o CM cmIco > o CO N t U) 4 . 3 12- 3 8- ^ A- A s C / ^ / ^ - J' ^ /* 1 / / ^ ^ T / 1 / I ^ y 1 ^ / 3 ■ 2 12- ] ^ 7 y y , -* I ^ ■ N V / ^ *N s. ^ •• A f V i _^ _ represents the weight curve of a premature infant, which was born in Guy's Hospital, and fed by an accommodating foster-mother in the manner de- scribed. On the eighth day of life the weight of the baby had fallen 14 ounces, and it was obvious that it would soon die if not provided with some better 1 H. C. Cameron, Tlie Lancet, September 27, 1913, p. 911. 14 THE INFANT form of nourishment than that supphed by the mother. The woman in the next bed happened to have a vigorous baby fourteen days old, and weigh- ing 8 pounds, and as she consented for the time being to play the part of foster-mother to the premature infant, an exchange of babies was immediately effected. Eight days later the premature baby was returned to its own mother, whose breasts by this time had been stimulated into functional activity by the importunate addresses of the borrowed in- fant. A glance at the chart will indicate the success of the experiment as far as the weakling infant was concerned. To complete the picture we ought also to be provided with the weight chart of the other infant. Dr. Cameron further suggests that when a baby of this kind is not procurable to perform the required duties, the services of an older child recently weaned may be conveniently enlisted for the purpose. He says : ' ' More than once among the poor out-patients I have induced the mother to put back to the breast a child which has been recently weaned." Opportunities to employ this ingenious expedient must be comparatively rare, for women seldom nurse their infants during pregnancy, and therefore can seldom have a recently weaned child at hand when the next one is born. In this comiection it may be mentioned that cows usually supply excellent milk almost up to the date of arrival of the next calf. The physiological activity of the mammary glands BREAST-FEEDING 15 is dependent on a very complicated nervous mechan- ism, in which mental and psychological factors are closely concerned in addition to the direct centripetal influences. It would be difficult to define accurately the origins or paths of these mental impressions which reinforce the efiect of the direct reflex stimulus. We know, however, that emotions and emotional states can sensitize or activate local nerve centres, so that otherwise subnormal stimuH reaching them through the direct reflex route, can cause normal or even exaggerated results. There is a very close relationship between the specific secretory functions of a gland and the vascular supply. The two sets of centres, in fact, act as if they were in anatomical continuity. The influence of the emotions on the vaso-motor functions explains the dominant influence of psychological impressions on the secretory functions of the r mammary glands. That curious complex of emotions known as the J maternal instinct has an undoubtedly favourabler influence on the secretion of milk, just as fear, anxiety, hatred, and anger have a reverse effect. Most women who have nursed infants successfully are familiar with the phenomenon know^n as " the draught " — a feehng of fulness that takes place in the breasts when the infant begins to suck. This phenomenon has probably little to do with the sudden resolution of the substance of the gland 1€ THE INFANT cells into milk as is generally supposed; it rather represents a sudden engorgement of the blood- vessels, and a flushing of the breast in consequence of vaso-dilator influences. This vaso-motor phenomenon can manifest itself with the same rhythmical and automatic periodicity that is familiar in the case of certain other organic functions, for it is one of the properties of nerve centres, such as those which subserve the mammary activities, to acquire rhythmical habits when the stimuli which first evoke the functions follow one another in regular and orderly sequence. If, there- fore, the infant is given the breast at absolutely regular intervals during the first few days of life, there is a reasonable probabihty that the receptive and impressionable nerve centres which control the functions of mammary secretion will acquire a rhythm and automatism which can be made to subserve most useful purposes, and promote the chances of successful breast-feeding. The usual practice in maternity institutions is to feed the infant three times during the first twenty- four hours, four times during the second or third day, and, finally, when the functions of lactation have become permanently established, to give the baby the breast every two hours. For the reason already stated, I do not regard this plan as weU designed to promote successful breast- feeding and the establishment of rhythm. The BREAST-FEEDING 17 frequent changes in the intervals of feeding must interfere with the assumption by the nerve cells of periodic habits at the very moment when such habits are most easily induced. If advantage is taken of this opportunity to impress a habit of regular activity on the nerve centres, the breasts may be induced to assume such a regular perio- dicity, that the times of feeding, as they come round, can be recognized by the arrival of " the draught." Mrs. Lucy Naish^, whose opinion on matters connected with breast-feeding deserves the fullest attention, advises against the practice of putting the infant to the breast more than three times during the first few days after the confinement, on the grounds that nursing exhausts the mother, and that the nipples are liable to become sore and excoriated if they are exposed too frequently to the friction of the infant's Hps. I cannot agree with these objec- tions because I consider that the physiological and the psychological influences of suckling altogether outweigh the other disadvantage that nursing may cause to the mother, and because I believe that if the nipples have been properly prepared before the con- finement, there need be no soreness due to suckhng. Provided that both breasts are in a state of func- tional activity, " the draught " occurs on both sides simultaneously. Of this associated action advan- tage may be taken in several ways. For instance, 1 The Lancet, June 14, 1913, p. 1657. 18 THE INFANT it is sometimes of importance to obtain breast- milk for infants who are themselves unable to extract it from the breast. In such cases the breast-pump is usually employed, but, as I have already men- tioned, the quantity that can be obtained by this means is less than that which is extracted by the infant; but if a strong infant is put to one breast and the pump is applied to the other, the physio- logical stimulus afforded by the infant promotes a more abundant flow into the receiver of the pump, and this milk, whether from the infant's own mother or from some other nursing-woman, may be instrumental in saving life. Indeed, it has been claimed that this method may be employed as a modified form of test-feed; that is to say, the amount of milk extracted by the pump from one breast may be an accurate gauge of the quantity obtained by the infant from the other. During the summer of 1913 two twins were brought to my consultations : one of them was strong and lusty, the other small and feeble. We gave each of them a test-feed, one being put to the left breast and, subsequently, the other to the right. The amount the strong baby secured was apparently adequate for his requirements, whereas the weakling obtained an insufficient quantity. Believing that the weakhng was suffering from inanition due to his feeble attempts at sucking, I instructed the mother to feed both of the twins simultaneously, holding one to the right breast and the other to the left. I BREAST-FEEDING 19 also instructed her to be prepared to feed them in this way on the next occasion she attended at the dispensary. On the following week we found that the smaller of the twins had improved considerably in condition, and that he had put on more weight than his brother. The mother further told me that since she had adopted this double method of feeding " the milk seemed to pour into the small baby's mouth without his doing any work at all," evidence which the test-feed confirmed in the weighing-room at the dispensary. Reverting once again to the question of the times of feeding and the acquisition of rhythmical habits, I would insist on the great advantage conferred on the mother as well as on the child by the adoption of the three-hourly method of feeding. In Germany there is a tendency to make the intervals even longer than this, and to allov/ four hours' rest between two consecutive feedings. On the whole I do not think this plan answers very well in the case of Enghsh nursing-mothers, and even in Germany, with extended experience, it seems that most infants obtain more milk and put on more weight when they are fed eight times than when they are fed five times during the twenty-four hours. Professor Hans Reitchel,^ who has paid attention to this question, comes to the conclusion that we cannot lay down hard-and fast rules. Each case must 1 Professor Hans Reitchel, Lehrbuch f. Kinderheilk., April, 1912, p. 403. 20 THE INFANT be treated on its own merits, and the number of feedings must be determined by the prevailing con- ditions. In the case of first children his inquiries indicate that four-hourly feeding is seldom a success, at least for the first few weeks of life. Whatever arguments may be urged against limita- tion to five feeds in the twenty-four hours, little can be said in favour of the two-hour system, for in so short an interval the stomach cannot be completely emptied except in quite rare instances, and it is essential that this important digestive organ should have time to recover after one period of activity before it enters upon another. It is unfortunate that the two-hourly method of feeding has been sanc- tioned by English custom, and that it has so many attractions for the impatient mother. Notwithstanding the arguments I have already cited in favour of the establishment of rhythm in the times of feeding, I see the advantages of longer intervals at night in order that a prolonged period of sleep may be secured. The value both to the mother and to the child of one long uninterrupted speU of sleep cannot be exaggerated, and the earlier this habit is induced the better it is for both. Habits of sleep are very easily acquired, especially when ad- vantage is taken of the quiet and darkness of the night. On the other hand, when once the infant has formed a habit of waking up in the night to be fed, it is very difficult to induce it to dispense with these attentions. It is not so difficult as is supposed to BREAST-FEEDING 21 train an infant to sleep right through the night, say, from 9 p.m. to 6 a.m. if the room is kept quite dark and quiet, but it is very difficult to persuade any mother that it can be good for an infant to be kept without food for so long a time. Provided, however, that an infant obtains a sufficient amount of food in the twenty-four hours to satisfy its physiological requirements, it is a very distinct gain that there should be one long interval of rest such as this. As a counsel of perfection I believe that the best hours for feeding an infant are six, nine, twelve, three, six, nine — that is to say, six feedings during the day and an interval of nine hours during the night for sleep. Although an infant will, perhaps, require to "be changed " or held out during this long night interval, the function of micturition can be made so auto- matic that it soon becomes a reflex habit and the child does not wake up. The establishment of a broken rhythm of this kind is not so irrational as might be imagined. All of us can acquire such periodicities, but infants acquire them more easily than older individuals. It is quite a mistake to suppose that young infants — that is to say, infants under one month of age — normally derive much nourishment from their mother's breasts. During the colostrum period, which usually lasts three or four days, the amount of secretion is quite insignificant, and even after the estabhshment of lactation, the quantity of milk obtained is far less than is usually supposed. Judg- 22 THE INFANT ing by the statements which appear in textbooks on the subject of infant-feeding, one would imagine that, by the end of the first week of hfe, the majority of infants extract about a pint of milk from the breasts. Table I. Day. Total Quantity of Milk taken in 24 Hours. Average Num- ber of Feeds Each Day. Averag') Quan- tity of Each Feed. Average Daily Weight. Oz. Dr. Dr. Lb. Oi5. 1st .. 9 3 23 2-28 7 1 2nd .. 1 15 5 00 5-23 7 1 3rd .. 4 12 8 88 819 6 10 4tli .. 6 4 9 24 9-98 6 15 5tli .. 6 11 9 33 11-70 6 15 6tli . . 7 3 9 22 12-39 7 1 7tli .. 7 9 9 53 1243 6 15 8tli .. 7 13 9 44 13-29 7 3 9tli .. 8 1 9 43 13-80 7 2 lOth . . 8 4 9 11 13-93 7 2 lltli .. 7 14 9 40 13-36 7 12th .. 8 8 9 38 14-88 7 4 13th .. 8 13 9 23 14-69 7 4 14th .. 8 11 9 48 1470 7 9 15th . . 9 3 9 29 15-70 7 3 16th . . 9 8 9 52 15-95 7 7 17th .. 9 4 9 54 15-94 7 6 18th .. 9 10 9 58 1608 7 4 19th .. 9 12 9 69 1607 7 3 20th .. 10 4 9 00 1843 7 4 21st .. 11 5 8 00 18-10 7 9 22nd . . 10 6 9 •28 18-40 8 1 23rd .. 11 7 10 00 18-30 7 8 24th . . 12 2 10-00 19-40 7 6, 1 This table shows the average amount of breast-milk secured by sixty-one infants in twenty-four hours, and at eacli feeding. It also shows (column 4) the average weight of the infants and the number of feeds (rolumn 2) in the twenty-four hours. It is to be noted that in columns 1, 3, and 4 the figures refer to avoirdupois and not apothecaries' weiijfhts. BREAST-FEEDING 23 The evidence on which this beHef is based is that which has been afforded by a comparatively small number of test-feeds conducted in maternity institutions in Germany. For instance, Camerer's figures, which constitute the usually accepted stan- dard, are derived from six cases only, and Freer 's estimates are based on a similar number. Repeating these experiments at my suggestion, on a much larger scale — namely in the case of sixty-one infants — Dr. W. 0. Pitt^ was able to show that the average amount of milk secured by London mothers confined in a maternity institute (the St. Mary leb one Work- house) was very much lower than the German stand- ards. Dr. Pitt's results are given in Table 1. (p. 22). In Table 11. Dr. Pitt's results are placed side by side with those of Camerer and Freer. Table IL Average Number of Ounces of Milk consumed by Nurslings during the First Ten Days of Life in Twenty-four Hours. Day of Life. 1st. 2nd. 3rd. 4th. 5th. I 6th. 7th. 8th. 9tb. lOth. Dr. Pitt's i 61! cases . . i i n 4^ 6* 6 n 8 7 8 8* Freer' s 6 cases — | 5f IH 15 161 20 18i 21 20 Camerer's 61 ' cases Is Ol 4^2 6 iH 12i 13 16 161 16 15f It will be noticed that Camerer estimates that the amount of milk obtained by infants on the seventh 1 The Lancet, September 2, 1911. 24 THE INFANT day of life is on an average 16 ounces and Freer 20 ounces, whereas Dr. Pitt's figures for the corresponding day amount to only 7 ounces. I call attention to these figures because it is gene- rally supposed that infants are being starved if during the early days of life they do not obtain amounts of food which conform to the textbook standards. Such a belief is quite unjustified; the infants in Dr. Pitt's series of cases (see column 4 of Table I.) showed quite normal progress and average gains in weight in spite of the small quantity of milk they obtained. Any unwarrantable interference with Nature's supply by supplementary feeding during the early days of life, until lactation is fully estabhshed, is extremely likely to interfere with the ultimate success of nursing. If the foregoing explanations of the factors on which successful breast-feeding depends are under- stood, it will be realized that the usual expedients adopted to secure the establishment of lactation are little calculated to promote the desired object. A short time ago I asked a class of experienced midwives what was the most important factor to attend to in the establishment of lactation. They all seemed to think that the feeding of the mother was the most important consideration. If what I have already said on this subject is physiologically and substantially correct, it is quite clear that gruel, or Benger's food, or nursing-stout. BREAST-FEEDING 25 can have no influence in the matter. The conditions on which the estabUshment of lactation depend are normal stimulation of the nipples, normal conduction of the nerve impulse, and normal reflexion of the impulse by the nerve cells in the centres concerned ; that is to say, the normal behaviour of a normal reflex arc controls the vascular supply and the secre- tory functions of normal glands. You cannot force these glands to activity by saturating the blood with nutritive material. It is, of course, essential tha^t the blood should con- tain the raw elements required for the manufacture of milk, and, further, if a large quantity of any manu- factured article is required, a large quantity of raw material must be supplied. But for the mere estab- lishment of the function of lactation it is not only unnecessary, but even harmful to attempt to over- feed the patient, for the blood always contains an ample quantity of nutriment. Of recent years a good deal has been written and said on the subject of galactogogues, and several preparations have been largely advertised as being capable of influencing the supply of milk. As far as I am aw^are, no specific galactogogue has yet been dis- covered, neither linseed-oil, nor cottonseed-oil, nor any of their derivatives can be regarded as galacto- gogues in the proper acceptation of the term. They are foods just as cod4iver oil or olive-oil are foods, and they can serve as the raw material out of which 26 THE INFANT certain of the constituents of milk can be manufac- tured; but they cannot influence the establishment or the non-establishment of lactation, although many poor people are induced to purchase these preparations and to take them under the belief that the money is well expended, and that they have some specific charm in the secretory powers of the mammary glands. An examination of the factors on which the estab- lishment of lactation depends emphasizes the im- portance of the following points : To set the secretory mechanism in motion it is necessary that the liberating stimulus received from the nipple should be adequate in intensity to evoke the required response from the controlling nerve centres. The responsiveness of these centres can be materially promoted by the favourable co-operation of the higher centres which subserve psychic and emotional activities ; they are, in fact, activated and reinforced by the concentrated fire of nerve energy which can be directed upon them by the psychic batteries of the higher brain. There is reason to believe that internal secretions, or hormones, circu- lating in the blood can also reinforce the activities of these centres or of the gland cells. There are, how- ever, no grounds for believing that foods or so-called galactogogues can have any influence in setting in action the nervous mechanism of secretion, although if a large amount of milk is required, the mother must be well fed to prevent exhaustion. BREAST-FEEDING 27 I have already dealt somewhat fully with the details concerned in the "estabhshment of lactation." I now propose to consider other matters connected with its subsequent maintenance and the general management of breast-feeding up till the time of weaning. It will be unnecessary for me to allude further to the necessity for long intervals between feeding and for giving an extended period of rest during the night, but I would refer to some very interesting observations made by Dr. Maynard Ladd^ of Har- vard, which show that the stom^ach requires even a longer period than is usually supposed to become completely empty, sometimes as long as six hours. The management of the quantity of milk supplied is a matter of prime importance, not so much during the first few weeks of life, when the chief desideratum is the estabhshment of the normal functions of digestion, as from the end of the first month onwards, w^hen considerations of nutrition should occupy our attention. There is a very general belief that, as the infant grows older and larger, there is a corresponding in- crease in the amount of breast-milk consumed. This is by no means an invariable rule, as my own obser- vations^ on a large number of infants of the poorer 1 " The Influence of Variations of Diet upon Gastric Mobility in Infants," Archives of Pediatrics, 1913, p. 740. - The British Manual of Children's Diseases, February, 1914, vol. xi., pp. 49-62. 28 THE INFANT class very clearly prove. There is, indeed, a serious risk of breast-fed infants being underfed during the later months unless precautions are taken to prevent tliis catastrophe. I imagine I do not overstate the case when I say that of all the factors in the environment which make or mar the development of the infant, food or feeding is the most important. Even in breast cases the feeding requires management, both as regards quality and quantity. It is very difficult to influence the quality of breast-milk — this is for the most part beyond our control — but we can manage the quantity or, at least, we can, with very little trouble, make ourselves acquainted with the exact quantity of food consumed, especially when we are dealing with infants of well-to-do parents. For many years past I have estimated, by means of the test-feed, in many cases repeatedly performed, the amount of milk consumed by all breast-fed infants brought to my clinics, both at the Queen's Hospital and at the St. Marj^lebone General Dis- pensary, and by this means I have gained some ex- perience of the quantitative variations in the milk- supply of different women. These variations are so bewildering and often so unexpected that it is merely playing with an important matter to attempt to treat breast-fed infants for nutritional and other disturbances until this primary element in the diag- nosis has been settled. I have, indeed, had some very strange experiences, which all go to show how BREAST-FEEDING 29 utterly futile it is to attempt to estimate the quantity of food an infant is obtaining without the confirma- tory evidence of the test-feed. Many times have I thought that the infant was being starved when in reality it was being " overfed," and often I have thought that " overfeeding " was the trouble when events have proved that the symptoms were due to starvation. There are, indeed, certain clinical tests by which we may distinguish between underfeeding and overfeeding, and I do not hesitate to refer to these very obvious indications, because I notice that they are often ignored. The cardinal symptoms of underfeeding are — 1. Loss of, or at least a failure to gain, weight at the normal rate. 2. Constipation, or in case of extreme starvation the passage of small mucous stools. 3. A Umited excretion of urine (oliguria). Whereas the cardinal symptoms of overfeeding are — 1. At first unduly large increments in weight suc- ceeded by a period of stationary or falhng weight. 2. The passage of large bulky stools and the pres- ence of redness of the buttocks. Constipation some- times develops, but the motions are large when passed. 3. The passage of a large quantity of water (polyuria) . 4. Sweating and vascular dilatation of the capil- laries of the face. 5. Rapid breathing. 30 THE INFANT In addition to these cardinal symptoms there are other means by which we may distinguish between starvation and superaHmentation — for instance, the condition of the mother's breasts conveys very im- portant information. Breasts which are full and large before feeding, and small and flaccid after feeding, presumably afford a good supply, whereas small breasts which do not perceptibly diminish in size after feeding as a rule cannot be credited with a liberal secretion ; but no matter how carefully we piece together such fragments of diagnostic evidence, it is impossible to rely on any other evidence than that of the test-feed. To show how very misleading the subjective sens- ations of the mother may be, and how utterly worth- less her own opinions as to the amount of milk she may supply, I herewith give the particulars of two interesting and illustrative cases : Case 1. — A male infant, two months old, was brought to the Queen's Hospital, February 10, 1913, for continuous screaming. The weight at birth was not noted, but the baby was reported to have been of average size; the weight on being brought to the hospital was 10 pounds. So presumably the infant had increased in weight some 2 or 3 pounds in the two months, and therefore could not have been systematically starved. For some days past the infant had been constipated, and had passed a very small quantity of water. The mother's breasts were of normal size and appeared well developed, but BREAST-FEEDING 31 milk could only be expressed with difficulty. I gave the mother instructions when she next came to see me not to feed the infant for three hours before attending at the hospital. In the meantime, feehng fairly confident from the symptoms that the infant was now being starved, whatever might have been the case at an earlier date, I told the mother to give the infant one teaspoonful of condensed milk and two tablespoonfuls of water after each breast-feeding. Owing to a mistake on the part of the mother, it was not possible to give a test-feed when the infant was brought to the hospital a week later, but in the interval the infant had gained 2 pounds 4 J ounces in weight, the largest increment I have ever seen registered in one week — in fact, no infant could possibly show such an increment unless it had been very seriously starved for some time previously. I have no doubt that the infant's tissues were very dry and that this extraordinary increase in w^eight was chiefly due to their rehydration. Two days later a proper test-feed was given, but this showed that the infant weighed the same after the feeding as it did before it was put to the breast — a result which was confirmed in the following week by means of a second test-feed. It is interesting to note that on the occasion of each of these test-feeds the mother told me, in answer to my inquiry, that the infant had had a good feed, and that she felt sure it obtained quite as much as it had during the early days of life when the whole history of the case proves that it must have been making good progress. Seven days later another test-feed was given, 32 THE INFANT but the result still proved that the breasts were quite dry. In the interim, however, the infant had gained further weight and was now 13 pounds 4 ounces. The mother was apparently so satisfied with the result of the artificial feeding that she ceased her attendance at the hospital, and I have not seen the infant since. Tliis result illustrates one of the great dangers of supplementary feeding with condensed milk. Owing to the sv/eetness of the milk, infants take so kindly to the food that they do not seem to apply much energy to the task of obtaining milk from a relatively dry breast ; moreover, the mothers are so pleased with the immediate results that they are only too glad to relinquish breast-feeding, with all its attendant troubles and disappointments. I have very Httle doubt that the infant above referred to grew into a fat, contented, flabby, and unhealthy baby, like the rest of its kind who are fed on this most unsatisfac- Ctory food. I have great faith in condensed milk as an easy stepping-stone to better things, but as a permanent bridge between the period of early weaning and the solid food stage, it is full of temptations and dangers. The three main defects in condensed milk, at any rate the ordinary sweetened variety, are — (1 ) That it contains a great excess of sugar, (2) that it is too easily digested and does not develop the functions of digestion, and (3) that it is a dead food which contains no antiscorbutic elements (vitamines). BREAST-FEEDING 33 The following case illustrates the value of the test-feed from a totally different point of view : Case 2. — W. W. — A male infant six months old and weighing 16 pounds 6 ounces was brought to the Queen's Hospital for constipation and glands in the neck. The infant was fed every two hours, and the mother was under the impression that she had not sufficient milk. I gathered from the mother's account of the condition of the napkins that the infant passed a large quantity of water, and from the appearance of the breasts and the ease with which milk could be expressed, I felt convinced that from whatever else the infant might be suffering, its present condition was not due to want of milk. I gave the mother the usual instructions, and two days later a test-feed was given at the hospital. This proved that the amount of milk which the infant ex- tracted from the breast was very nearly 7 ounces, a quantity wliich in my experience of hospital practice in the East End of London is almost unique, and it suggested a diagnosis of overfeeding, and, on reflection, the symptoms appeared by no means inconsistent with this explanation. Con- stipation is not an uncommon accompaniment of super-ahmentation, but in this particular case, as I subsequently discovered, the constipation was due to the abuse of soap-and-w^ater enemata. There are, on my experience, few more aggravating causes of constipation in infants than the early dislocation of the normal rectal reflex by the administration of enemata, glycerine suppositories, and powerful aperi- ents. I treated this case by extending the intervals 3 34 THE INFANT between feeding, by reducing the amount of clothing, and by promoting the physiological demand for food in the many ways I have already mentioned. Thus were overcome the consequences of overfeeding, and the infant soon improved in condition. It at once increased in weight, and was in perfectly good health when the mother ceased attending at the hospital. I could easily multiply instances both of overfeed- ing and of underfeeding which have been revealed and cured owing to the instrumentality of the test-feed, but no degree of repetition would be so convincing as a short experience of the method in an infant clinic. Personally, I cannot understand how anyone can expect to treat breast-fed infants successfully unless he or she first takes the precaution of becoming ac- quainted with the amount of food the infant consumes* I imagine that the two really important factors in the infant's environment are the quantity and the quality of the food. It is very difficult to obtain accurate information with respect to the quality of breast-milk, for chemical analysis shows us but little ; but it is quite easy to obtain precise information with respect to the quantity, and I consider that any physician who fails to take this precaution, does himself an injustice. Although for the last ten years I have practically never omitted to gauge as accurately as I have been able the amount of milk which has been consumed by every breast-fed infant concerning whom I have BREAST-FEEDING 35 been consulted, I freely admit that even with the ex- perience I have thus gained I am unable to form a reliable estimation of the quantity obtained by any particular nursling by any clinical test with which I am acquainted other than the test-feed, I have elsewhere explained that, within certain wide limits, the supply of breast-milk is correlated to the demands of the infant ; that is to say, other things being equal, the more hungry and lusty the infant, the larger will be the amount of milk afforded by the breasts. In other words, there is some parallelism in this particular secretory function between the intensity of the stimulation applied and the reflex response elicited. But this physiological correlation does not obtain under all conditions ; its fulfilment demands the existence of normal conditions in the secretory apparatus and its nervous mechanisms. For instance, the casual presence of a crack in the nipple may induce painful impressions, and these may suppress rather than excite secretion in the mammary glands; on the other hand, psychological disturbances in the mother may interfere with the normal liberation of the reflex response. Again, the infant itself is, like the mother, subject to psycho- logical disturbances, and for some quite unforeseen reason may refuse to suck and apply the required stimulus. Suggestion plays a most important part in the actions of an infant. For instance, one or two disappointments at the breast may shake the infant' 36 THE INFANT faith, and it may refuse to make any further efforts. Sometimes the effort of sucking may initiate painful sensations in the abdomen, due to contraction of sphincters, to enterospasms, or to other forms of inco- ordinated peristalsis ; and when once the infant asso- ciates such experiences with the act of taking the breast, it may resolutely refuse to make any further attempt. The truth is that breast-feeding requires a great deal of management if it is to be a complete success. It is a mistake to underrate its difficulties or to exaggerate its merits. One of the most important matters in connection with breast-feeding is to know when and how to supplement an inadequate supply with artificial feedings. In this connection two factors must be considered — firstly, how much food ought any particular infant to receive in the twenty-four hours ; and, secondly, how much does it actually derive from the mother's breasts. As regards the first factor, I must refer the reader to Chapter III., which treats of the food requirements of infants. If it is found by means of the test-feed that the quantity of milk supplied by the mother falls materially short of this amount, then the deficit must be made good by supplementary feedings. It is very difficult to in- crease the natural supply by any practical expedient. Galactogogues which directly stimulate the flow are unknown, and food makes very little impression. Starving women afford quite a good supply, as we know from the experiences of the siege of Paris in BREAST-FEEDING 37 1870, and the great cotton famine in Lancashire some years prior to this date. During these times of trouble and deprivation the infant mortality was peculiarly low, and the infants did not seem to suffer in health from the starvation of the mothers. I had quite recently an interesting illustra- tion of the insignificant influence of starvation on the mother's milk, when a woman, whom I had known for some years, came to my infant consulta- tion with a three-months-old baby whom she was suckling. This woman was suffering seriously from the effects of inanition, and yet the baby was plump and well, increasing normally in weight, and appearing quite well in all other respects. The test- feed showed that the amount of milk obtained at a feeding was ample. Dr. Leslie Duncan^ has made some interesting observations on the influence of dinners supplied to necessitous nursing-mothers in Birming- ham. The extra food supplied in this way to half- starved women had a distinct influence on the fat con- tent of the milk, but in no other way appeared to influ- ence its quality, although the nutrition of the mothers materially improved in consequence of the extra food. This has been my own experience also, although I have not had an opportunity of confirming my cUnical experience by many actual analyses of the milk. On the other hand, if a nursing-mother is already obtaining a sufficiency of food, no good purpose will be served by amplifying her already adequate 1 Eeport on Infant Mortality. Birmingham, 1913. Printers : Hudson and Son. 38 THE INFANT dietary. Nursing-stout, gruel, and cod-liver oil often do more harm than good by making the mother bilious and thus upsetting the general bodily equi- hbrium on which a good mammary secretion so largely depends. I would, however, say one word in favour of iron as an adjuvant to the nutrition of the nursing-mother; it is certainly a drug which may improve the quality of the milk. At the best of times breast- milk is none too rich in iron, and it may show a noticeable deficiency if the mother has been depleted of it by haemorrhages or other conditions which dispose to anaemia. Infants very soon show the effects of iron starvation, and their general con- dition of nutrition may under certain circumstances greatly improve when it is administered to the mothers. I make a common practice of supplying nursing-mothers with 15 to 60 grains of carbonate of iron in the twenty-four hours, and I generally notice that the quality of the milk — as estimated by the nutrition of the infants — improves. Seeing that by ordinary means we cannot increase the quantity of the natural supply, we must compensate for a shortage of breast-milk by giving supplementary feedings ; and it is certainly my experience that some of the best results in breast-feeding which I have seen have been in the case of infants fed by the combined method. The supplementary feedings can be given in various ways, either at the beginning or at the end of a breast-feeding, or as an occasional substitute for it — that is to say, by alternating breast- and bottle- BREAST-FEEDING 39 feedings, or by substituting one, two, three, or more, bottles for the breast. I would not like to lay down any hard-and-fast rules. Each case must be judged on its own merits. Sometimes on inquiry, or on the evidence of a test- feed, we find that at one particular hour in the day the mother's milk materially fails. If this is so, this hour should be chosen for the supplementary bottle. I find from experience that the late afternoon feeds are the poorest in quantity, just as the first morning feed, after the long rest at night, is usually the largest. Sometimes I find it an excellent plan to give a small supplementary feed at the end of each feeding. I have had some very extraordinary cases both at the Queen's Hospital and at the St. Marylebone General Dispensary, in which the addition of an in- significant quantity of extra food has produced a quite disproportionate change in the infant. Infants whose weight may have been stationary for weeks or months may increase a pound or more in weight in quite a short time by the addition of a few ounces of cow's milk in the twenty-four hours. It is naturally of some importance to supply the right food in the right amount when recourse is had to supplementary feedings. The amount of food to be given by hand will depend on the quantity of breast -milk already taken by the infant. It is unwise to augment the quantity too suddenly or too drastically. The danger of overloading an unpre- pared stomach is very great. 40 THE INFANT If an infant obtains, say, 15 ounces of breast- milk from the mother in the twenty-four hours, when, according to ordinary estimation, the amount should be at least 25 ounces, we must consider in what way to supply the deficiency. If we find, after giving a few test-feeds, that sometimes the infant obtains a large quantity and sometimes a small, it may be quite safe to give the supplementary food in comparatively large quantities, say, in doses of 3, 4, or 5 ounces. On the other hand, if the infant appears to obtain its total supply in small and constantly regular quantities, it may be better to distribute the supplementary food in the form of small and increasing addendums to each feed; but, as I say, there is no rule, and each problem must be solved by a full consideration of the individual difficulties. I find among the poor that the simplest and most practical method of supplementing a defective breast-supply is to order a quarter, a half, or a whole teaspoonful of condensed milk to be given after each breast-feeding, the food to be given in a spoon without any previous dilution. This obviates the possible danger of overdistending a stomach already full of a thin and poor milk, for it must be remembered that infants are often underfed, owing to the poor quality of the milk, although its quantity may be ample. This is especially the case towards the end of lactation, when the mother has become exhausted from prolonged suclding. CHAPTER II Some Physiological Principles concerned in THE Nutrition of Infants When we speak of the state of nutrition of an animal or of a human being, I imagine that few of us con- jure up a very clear picture of the exact meaning of the term we employ. We are apt, for instance, to regard the popular expression " to be well nourished " as synonymous with " being in a condition of good nutrition." As a matter of fact, "to be well nourished," in the more usual acceptation of the expression, is to be fat and sleek — to be in the sort of condition in which prize cattle and babies are when they are sent to shows — a very different thing from being in a sound condition of health. I should find myself in a very difficult position if I were asked to define shortly what I myself understand by the term " good nutrition." It certainly has very Httle to do with reserve stores of fat or glycogen, and it certainly has a great deal to do with the functional efficiency or " fitness " of the individual. Wlien an organism as a whole is said to be in a condition of good functional efficiency or good nutri- 41 42 THE INFANT tion, such a statement implies that the individual organs or elements that make up the sum total of its anatomy are also in a condition of functional efficiency. We ought therefore to judge the condi- tion of nutrition of a baby, for instance, by the standard of its functional efficiency rather than by that of its outward appearance. There is truth in the statement that no one can judge of the time- keeping qualities of a watch by a mere inspection of its mechanism, and for the same reason there is truth in the view that there are few people who can judge of the physiological efficiency of the human baby by a simple examination of its exterior char- acteristics. There are, however, a large number of physiological functions which betray their merits or defects by visible and objective manifestations. For instance, if the liver does not play its part efficiently in the destruction or combustion of the products of intestinal putrefaction, the individual will be un- duly pigmented or muddy of complexion; or, again, if the kidneys are diseased or incompetent, the tissues may be oedematous or the complexion bloated. It requires, however, a very shrewd observer to judge at all accurately of the condition of nutrition of any particular individual by an examination of externals. He must judge by performance, and not by appear- ances. In order that any organ or tissue may be in a con- dition of good nutrition or good functional efficiency, THE NUTRITION OF INFANTS 43 certain conditions are essential. In the first place, good nutrition postulates that the organs or tissues themselves must possess normal quahties, qualities which will enable them to perform the duties de- manded of them. Secondly, they must be provided with the food or nutritive material which is required for their normal metabolic processes. And, thirdly, they must be in connection with a normally con- stituted nervous arc. The soundness and integrity of this nervous arc is of paramount importance for the nutrition of the highly complex organs of which our bodies are composed. Let me take, for instance, such an example as the biceps muscle. For this muscle to be in a con- dition of functional efficiency, it must constantly exercise its function, or it will assuredly atrophy. The functions of this muscle are not only exercised when it becomes mechanically shortened and it performs external work, but its activities are in con- stant operation in the mere maintenance of "tone." " Tone," however, ceases to exist the moment the integrity of the reflex arc is damaged or destroyed. A never-failing stream of sensory or centripetal impulses constantly impinges on the nerve ceU, which controls the administrative functions of the reflex arc. These centripetal impulses are inter- preted by the nerve ceU and transmitted to the muscle in the form of an endless succession of trophic or tone-giving stimuH. The moment these U THE INFANT centripetal impulses are cut off, as by severance of sensory nerves, or the moment the functions of the nerve cell are dislocated, that moment does the muscle cell lose its tone, or, in other words, fail in nutrition. Whether, therefore, we take the case of a single muscle or of the body as an aggregate of many organs, we can see, in the hght of these fundamental conceptions, that nutrition depends on a large number of factors, chief and foremost among which is the integrity or efficiency of the nervous arc. Now, bearing these facts in mind, I would ask you to turn your attention for a moment to a con- sideration of the first of the factors which I have already enumerated as requisite for nutrition — namely, the food or nutritive supply. In order that nutrition may be maintained, certain food require- ments must be observed. The food must contain all the elements required by the various organs for the performance of their functions, and in adequate amounts. If the supply falls short, or is excessive in amount, the organism suffers. But, owing to the vast reserve powers of the body, there must be a large excess or a serious shortage to produce any material damage. The human body has aptly been compared to a community of citizens, in which economy and efficiency have been secured by a strict adherence to the principles of the division of labour. The cells of the body, like the various professions or classes THE NUTRITION OF INFANTS 45 in a community of individuals, are differentiated into systems or groups for the performance of certain definite and often highly specialized functions. Thus, in the digestive tract we find segregated together cells whose special duties are to render soluble and suitable for the nutrition of the other members of the community, those soHd and crude articles of diet which are consumed as food. Again, we find in the liver a vast assemblage of cells whose special function it is to sort the good from the bad, and to destroy or oxidize those waste and superfluous products which, together with the necessary and useful products, are absorbed from the alimentary tract, and are passed through this great scavenging system. Highly organized cells, such as those of the nervous or muscular systems, could not perform their specialized duties with the required efficiency if their energies were diverted for such base and commonplace purposes as the digestion and preparation of their own food. It is the special duty of the cells concerned in the processes of digestion and assimilation to reduce the many varieties of food, consumed by the host, to some common denomination, or to some uniform standard capable of fulfilling the required conditions. The blood contains, or should contain, aU the nutri- tive material required for the growth and mainte- nance of the many varieties of tissue cells represented in the body, and in a form at once available for 46 THE INFANT utilization. The composition of the blood remains singularly constant and uniform, no matter what may be the nature of the food consumed. Chemi- cally and physically, the blood is most accurately adjusted to the requirements of the tissue cells, so that the latter always receive nutritive material, which is adjusted both quantitatively and qualita- tively to their specific needs. It would greatly interfere with the efficiency of their work if these cells were to be constantly confronted with changes in the character of their food, for such variations would necessitate corresponding adjustments in the disposition of their molecular structure. It is, therefore, impossible to insist too strongly that one of the most important mechanisms in the animal body is that which is concerned in maintaining the uniformity, or specificity, of the circulating nutrient media. The blood contains, or should contain, every one of the essential elements required for the synthesis or building up of the many varieties of tissue cells contained in the body; for this purpose, proteins, carbohydrates, fats, salts, and a great number of other colloidal or crystalloid bodies are required. Every provision is made for maintaining these necessary substances at a uniform strength and of specific quality, and for eliminating from the cir- culation all those which are not required. Any gross departure from the required standards may THE NUTRITION OF INFANTS 47 cause considerable dislocation of the machinery of the body, and interfere with the health of the organism as a whole. For this reason, the blood of one animal cannot be transfused into the circulation of another without risk. The more closely the animal whose blood is transfused into the circula- tion of another is allied by the ties of consanguinity or habit to the animal into which it is injected, the less serious are likely to be the disturbances provoked. Even the blood of two members of the same family, of two brothers for instance, is not exactly iden- tical, and cannot be substituted without some dis- turbance of organic equilibrium. The blood of the mother is practically identical with that of the foetus in her womb, and so is the blood of one dicephalous twin with that of the other; but the blood of the infant ceases to be identical with that of the mother the moment the placental connections are severed. The maintenance of the specificity and uniformity of the blood is so important to each individual that it is not without interest to inquire by what mechan- ism or mechanisms these conditions are fulfilled. Most of us are quite familiar with the resources at the disposal of the organism for maintaining the quantitative constancy of the blood. Thus, we all know that, as regards the carbohydrate content of the blood, the required percentage is maintained by elaborate systems of extra-circulatory storage, and 48 THE INFANT by elimination from the body ; the same is true, to a greater or less extent, with respect to the nitrogenous and saline constituents of the blood. These matters are so familiar that I feel my time will be employed better in confining myself to the manner in which the qualitative constancy of the blood is insured. To a certain extent, similar mechanisms and methods are employed to maintain the qualitative constancy of all the essential constituents of the blood ; but inasmuch as the specificity of the protein content transcends in importance the specificity of all the other constituents combined, I shall confine myself to this side of the question, although mutatis mutandis the details are practically the same for all the other nutritive elements in the blood. Thanks to the brilliant work of Emil Fischer, Emil Abderhalden, and other organic chemists working in the same school, we now have more exact information of the molecular constitution of protein bodies than we had, let us say, ten years ago. We know, for instance, that these complex bodies consist of long chains of relatively simple atomic-complexes, such as fatty acids and amido-acids, linked or combined together in ester groupings or piperazine rings. Further, we know the exact chemical con- stitution of the amido-acids which take part in these syntheses, and can recognize their presence by chemical tests. At least twenty separate and in- dependent amino-acids have thus been isolated, THE NUTRITION OF INFANTS 49 and recognized as taking part in the specific " make- up " of the various protein bodies. The number of combinations of amino-acids is, however, possibly greater than the number of combinations of letters into words, for, however sesquipedalian may be the character of the latter, their length is as nothing in comparison with the possible length of the chains of amino-acids which constitute the huge molecules of which proteins consist. Thus, although it is quite easy to separate the various classes of proteins into groups or classes, such as serum-albumins, globuHns, nucleo-albumins, caseinogens, albumoses, peptones, or coUagens, it is quite possible, or, indeed, almost certain, that there are slight specific differences in the " make-up " of each representative of each class, although the dis- tinction between these various representatives is at present indistinguishable by ordinary chemical tests. These specific differences unquestionably depend on the number and the grouping of the component amido-acids. We know, in fact, that the serum-albumins or globulins of no two animals are exactly identical when put to the test of the bio- chemical reaction; if, for instance, the serum of a horse is transfused into the blood-stream of a human being, it acts as a foreign body, and leads to the production of specific precipitins. This phenomenon has a most important bearing on certain phases of infant feeding, for we know that, under given eon- 4 50 THE INFANT ditions, unaltered proteins^ are absorbed from the alimentary tract into the circulation without previous digestion; further, we know that such absorption can be followed by untoward consequences, as, for instance, by the development of extensive urticarial rashes. Immediately after birth, and before the processes of digestion are established, if soluble proteins are introduced into the stomach of the infant, a certain proportion will be absorbed; if these proteids are foreign, such, for instance, as those contained in cow's milk or in white of egg, they will excite bio- chemical reactions, and lead to the production of specific precipitation in the blood, and therefore they will not subserve the functions of ordinary nutrition, and consequently are not only useless, but may be actually dangerous. On the other hand, if proteins, as, for instance, those contained in the colostrum of the child's mother, are introduced into the system of the infant and happen to be identical with its own specific circulating proteins, the case is quite different; such proteins are not foreign bodies, and are available for the purposes of nutri- tion. A consideration of these facts emphasizes the importance of maternal feeding. Even the colostrum of a wet-nurse does not contain exactly the same proteins as the colostrum of the mother, 1 Van Alstyne and Grant, Journ. of Med. Research, 1911, vol. XXV., p. 399. THE NUTRITION OF INFANTS 51 and consequently is not exactly suited to the re- quirements of the infant. It may be safer to feed the new-born infant with the colostrum of a wet- nurse than with the milk of some foreign species of animal, the cow, for instance ; but there are dangers attaching even to this procedure, and wet-nursing should not be attempted during the first few days of hfe. The important purpose of digestion is not so much to bring about the solution of solid articles of food as for the purpose of splitting up foreign material into its component elements. For instance, foreign proteins are split up by the processes of gastric and intestinal digestion into their constituent amino-acids, sometimes into chains of amino-acids of varying length and varying degree of complexity, sometimes into individual amino-acids, and out of these fragmentary particles new proteins are built up by synthetic processes on an entirely new archi- tectural plan, and of a type which is suited to the specific requirements of the individual in whom they circulate. I have already referred to the fact that in the " make-up " of the various protein bodies there are quantitative as well as quaUtative variations; thus, egg-albumin does not contain among its constituent amino-acids, representatives of the glycocoll group, while ghadin, a vegetable protein, does not contain lysin, nor does gelatine contain tyrosin or trypto- 52 THE INFANT phane. On the quantitative side, egg-albumin has been shown to contain only 8 per cent, of glutaminic acid, while in gliadin it is represented to the extent of 33 per cent. In the light of this knowledge, it is easy to under- stand that when one proteid is built up, so to speak, out of the ashes of another, there may be synthetic difficulties owing to the absence or relative deficiency of some particular amino-acid, or of some atomic grouping, or, indeed, there may be excess of certain amino-acids which must be disposed of. For in- stance, we cannot expect the organism to build up its own specific serum-albumin out of gelatine or out of a vegetable protein such as gliadin, for the former contains no tyrosin or tryptophane, and the latter no lysin, all of which amino-acids are required for the " make-up " of serum-albumin ; but we could well imagine, as, indeed, is the case, that the organism might maintain nutrition on a diet of gelatine to which the missing amino-acids, tyrosin and tryptophane, had been added, or on a diet of gliadin plus the requisite quantity of lysin. A knowledge of these facts explains why calf's-foot jelly, at one time so greatly valued as an invalid food, and subsequently held in such scientific contempt, can be an excellent food in combination with beef -tea, and yet of little nutritive value as an exclusive food ; it also explains the advantages of a mixed diet. The whole question of the resolution oj joreign pro- THE NUTRITION OF INFANTS 53 teins into their component elements, or arnino- acids, is of immense importance in infant dietetics, for unless foreign proteins can he so resolved in the processes of digestion, they cannot be utilized for the purposes of synthetically compounding the specific proteins, which are essential for the nutrition of the growing baby. Young infants are not at first possessed of these digestive powers, although they soon acquire them under suitable conditions of training. The protein foods usually provided for the infant consist largely of caseinogen, a substance which is converted into an insoluble casein by the ferment rennin con- tained in the stomach; it is then further acted upon by lactic acid, or hydrochloric acid and pepsin, and converted into albumoses and peptoses. Al- though these soluble and diffusible bodies may be taken up into the system, it is a question to what extent they can subserve the purposes of nutrition. If they are really to be useful, they must be broken down still further into shorter chains of amido- acids by the processes of pancreatic digestion. If pancreatic digestion is carried far enough, a very complete resolution of the protein molecule into its component amino-acids occurs, and out of these individual acids, or from short chains of acids, the new proteids are built up by the organism, either in situ in the wall of the intestine, or locally in each organ. When it is remembered how many different kinds of proteins exist in the animal body, it is 54 THE INFANT hardly remarkable that the specific albumin of the blood of each individual has complicated functions to perform, for out of its own molecular structure must be suppUed the required building material for the make-up of such very differently constituted bodies as the myosin of the muscles, the histone of the thymus, the collagen and elastin of the con- nective tissues, the keratine of the hair and nails, and the nucleo-proteins of the nervous system. The circulating proteins of the blood must, in fact, represent the least common multiple of all the prime factors into which the various tissue proteins can be resolved, although this analogy need not be taken too literally nor pressed too far. It is quite easy to understand that, when through monotony or defects in the dietary, the specific " make-up " of the circulating proteins is not exactly adjusted to the requirements of the organism, com- plications and disturbances of development may occur. Such a disease as scurvy, for instance, may possibly depend on the absence of simple atomic groupings which are required for the specific " make- up " of some nucleo-protein ; indeed, there is good evidence that the disease does depend on the con- tinued absence of certain derivatives of nucleic acid known as vitamines, wliich are present in fresh foods, but are more or less destroyed when the fresh foods are disintegrated by heat or prolonged keeping. We know that the reserve powers of the animal THE NUTRITION OF INFANTS 55 organism, both as regards compensation, metastasis of function, and excretion of waste products, are so great that ordinary degrees of excess or deficiency with respect to any particular food element do not greatly disturb the general equilibrium. At the same time the best results in nutrition are obtained when these reserve forces are least strained. The practical deductions to he draivn from these arguments are mainly concerned ivith the neiv-born infant, and it foUoivs from what has been already stated that it is quite useless, or even dangerous, to supply the neiu-born infant with any variety of foreign p^'oteid, unless or until the digestive functions have been established. It is possible that a great number of the troubles of digestion and nutrition in infants and young children can be traced to the improper administration of cow^s milk before the gastric ayid pancreatic functions have been developed. The common practice of greatly diluting cow's milk does not necessarily enhance its suitabihty as a food for infants. If it can be digested by the gastric and intestinal ferments, and broken up into its constituent molecular fragments, well and good ; but if it cannot be so broken up and rendered suitable for synthetic purposes, no degree of dilution will make it a suitable medium for nutrition. I cannot help thinking that in our attempts to make cow's milk digestible we often dilute it too much, 56 THE INFANT As I have already indicated, the digestive func- tions of the infant are not developed at the time of birth, and it may be days, weeks, or months, before the gastric or intestinal functions become sufficiently developed to deal satisfactorily with diluted cow's milk; the time will be more or less dependent on the experiences to which the digestive functions are submitted. If an infant is deprived of the educa- tional experiences to which it is entitled — namely, the gradual metamorphosis of its mother's colostrum into the ordinary milk of full lactation — it is quite clear to my mind that some other means of educa- tion should be found. If an infant cannot digest or break up foreign food into those elementary fragments out of which it can synthesize its own specific nutritive material, we ought, wholly or in part, to perform its digestive functions for it. In other words, we ought to pre-digest any artificial food which is given to the new-born baby. Now, it is very clear that foreign proteins cannot be broken up completely into their component amino-acids by any perfunctory or superficial act of artificial digestion. If i7i vitro we digest milk with pepsin or pancreatic extract for a period of twenty minutes, the time usually recommended, we hardly begin to digest the food. By such a procedure we only convert a tithe of the proteins into albumoses or peptones. If we wish to dis- integrate the greater proportion of the casein and THE NUTRITION OF INFANTS 57 whey-proteins into their component amino-acids, or even into comparatively short chains of amino- acids, it is necessary to pancreatize (pepsin is useless for this purpose) for twenty hours, not for twenty minutes. The necessity for the prolonged pre- digestion of proteins has been well pointed out by A. Rendle-Short and H. W. By waters in their article on the preparation of nutrient enemata.'' It is quite a mistake to think that milk completely digested in this way is too nauseating and bitter for infant consumption, for new-born infants will swallow most liquids with complete indifference, no matter how disagreeable adults may think them. Although, from the theoretical point of view, it may be desirable to pre-digest milk for twenty hours, if it is desired to convert all the proteins into amino- acids, from the practical standpoint six hours' pre- digestion, at a suitable temperature and with a liberal supply of pancreatic extract, is sufficient. But milk which is pancreatized for this prolonged period is apt to become contaminated and nauseating to the taste by the simultaneous development of putrefactive bacteria; for this reason, it is very necessary to sterilize the milk thoroughly before commencing the operation, and to boil it again at the end of the proceeding, or even during the period of digestion. It is further necessary to remember that the i The Lancet, June 28, 1913, p. 361. 58 THE INFANT infant should gradually be taught to digest its own food. For this reason the milk, which at first should be very thoroughly digested, should be pancreatized less and less with each succeeding day. I generally advise that the milk should be pre-digested for six hours at first, and for ten minutes less every day, so that in thirty-six daj^s from the time of com- mencement, the infant will be taking completely undigested milk. By this method, most excellent and reliable results can be obtained; it is, however, important to insure that the pancreatic extract is active, that the amount of food given at each feeding and the intervals between feeding are adjusted to the physiological requirements of the case. For many years past, clinicians have argued as to the respective merits of boiled milk, unboiled milk, milk scientifically modified, or milk diluted haphazard, as a food for infants; but now, thanks to the researches of the modern physiologist, we know that all of them can be good foods or bad foods, according to the previous experiences of the infants. An infant can be taught to digest any food, but it cannot digest a new food at the first trial any more successfully than a child can play the piano before it has learnt the notes. A very important physio- logical principle to remember is that almost every living cell can acquire, de novo, the special catalytic properties which are necessary for the splitting up or digestion of food substances. Some cells, how- THE NUTRITION OF INFANTS 59 ever, have greater powers in this respect than others, and the cells concerned in the processes of digestion are highly endowed with this function. For instance, enzymes or catalases are required for splitting up the different varieties of sugars, and these enzymes are improvised by the cells as necessity requires. Dr. R. S. Frew^ has shown that if the sugar of a young child is changed from one variety to another, the new variety will remain undigested for a few days, until the cells of the organism have accom- modated their metabolic processes to the change, and have learnt to supply the new catalytic agent. ^ In disease we see many evidences of the same phenomenon, although under such pathological con- ditions the tissue cells rather than the digestive cells are concerned in the production of the catalyzing agents. Immunity to disease is an acquired property of the cells, and so is their capacity to deal with foreign foods; in fact, the processes are supposed to be practically identical, and in both cases, when once the lesson has been learnt, the knowledge remains a more or less permanent possession. Thus, during childhood the organism learns how to protect itself against a great number of diseases — for instance, against measles, chicken-pox, whooping- cough, scarlet fever, tuberculosis, and a whole host of other diseases. As a rule the lessons, which are somewhat sharp and severe, are not forgotten, but 1 The Lcmcety November 4, 1911, p. 1264. 60 THE INFANT sometimes we come across refractory cases in which the individual only acquires immunity with diffi- culty, or not at all. This is perhaps more often the case with tuberculosis than with any other disease. In certain cases which are not thoroughly understood, one attack renders the individual more susceptible to, rather than more immune from, subsequent infection. This curious condition, known as "anaphylaxis," is well known in connection with hay-fever, asthma, and influenza, and it is also a well-known phenomenon in connection with drugs — for instance, one small dose of arsenic may render an individual highly sensitive to its action ; indeed, so much so that hereafter the smallest dose may produce toxic effects. There is a strictly comparable phenomenon in the case of different articles of diet: shellfish or almonds at times produce the most intense urticarial rashes, and some babies, and for the matter of that, some grown-up individuals, display such marked intolerance of cow's milk that as an article of diet it must be permanently given up. Anaphylaxis, both in the domain of pathology and of dietetics, is clearly a stage in, or a complement to, immunity ; but its exact significance and the best methods of dealing with it are not yet clearly understood. The phenomenon of anaphylaxis — or ''allergy,'" as it has been called by von Pirquet — in its relationship to food idiosyncrasies must clearly be distinguished THE NUTRITION OF INFANTS 61 from another form of intolerance to special articles of diet, which has a purely psychological basis. The lower nerve centres of the brain and their subcon- scious activities play a very important part in the behaviour of the infant. Young infants behave purely as automatons; in response to suggestion they act exactly like deeply hypnotized persons or well-trained animals. In older individuals, in whom the powers of reason have become developed, the direct influence of suggestion may be counteracted by innumerable inhibitions, but in babies, animals, and hypnotized individuals the call of suggestion is imperative, and the exact form the response takes is determined by the nature of the previous responses — in other words, by habit. Thus, to take a simple example, the sucking reflex is one of the earliest and most easily ehcited of aU the inborn mechanisms of an infant; the imperativeness of this habit is well illustrated in the tyraimical and pernicious influence of the " comforter." The presence of a teat between the lips acts as the suggestion to suck, and the younger the infant the more imperative the caU; but as the infant grows older, inhibitions and conflicting reflexes interfere with the purity and spontaneousness of the response. We find, for instance, that in giving test-feeds to infants at our infant consultations at the St. Marylebone General Dispensary, quite young infants take the breast better than older 62 THE INFANT infants, because the latter are more easily distracted by the strangeness of the environment — in othe^" words, by conflicting stimuli. As an instance of the influence of suggestion in quite a young infant, I would refer to the case of a baby, two months old, under the care of Dr. W. G. Cazalet, of Sutton: This baby had a very severe spastic diplegia, from which it subsequently died. My opinion was asked as to whether any further steps could be taken to restrain the severe spasm into which the muscles passed the moment they were brought into action. The condition had been treated with some success by galvanism — that is to say, in so far that the spasm relaxed by the application of the positive electrode to the affected muscles. The interesting feature of this case, and the one which illustrates the point I wish to make clear, is that relaxation of the spasm resulted equally well whether the electric current was turned on or not from the battery ; in other words, the laying on of the electrode acted by suggestion and not by reason of the direct action of galvanism. I could give many other examples of the uses to which suggestion can be applied in the training or treatment of infants; but when we realize that all their actions are dictated by suggestion, the multiplication of examples become super- fluous. In conclusion, h owever, I must give one instance THE NUTRITION OF INFANTS 63 of the manner in which suggestion acts in deter- mining the so-called " food idiosyncrasies " : A fat, flabby baby, fed on condensed milk, was brought to my infant consultations for treatment and advice. Among other details, I recommended that the infant should be gradually weaned from the condensed milk, and placed on a diet of desiccated milk. I gave explicit instructions as to how the substitution was to be carried into effect. Unfortunately, the mother gave too large a quan- tity of the dried milk on the first occasion, thus omitting to give the infant time to accommodate itself to the changed digestive requirements, with the consequence that the infant was violently sick. Hereafter the baby was sick every time it was supplied with the desiccated milk, no matter how little was given at a time. I came to the conclusion that this was due to suggestion and not to anaphy- laxis. And to prove the truth or the reverse of this view, I instructed the mother to try the effect of adding the dried milk in such a w ay that the infant could not foUow the operation with its eyes or ears, for I believed that the sight or the sound of the milk being taken out of the tin might be the effective stimulus. On the occasion of her next visit, the mother reported to me the success of the experiment, and told me that when the food was mixed in an adjoining room, the infant could take equal quanti- ties of dried milk and condensed milk without vomiting. As a control experiment, I now in- structed her to go through the process of opening the tin and of pretending to add some of its contents 64 THE INFANT to the condensed milk, but to be careful not to allow any of the milk powder to reach the bottle. The success of the experiment was again most striking in proving the psychological basis of the idiosyn- crasy, for now the infant vomited just as persistently as he did when the milk was really added. Cases of this kind — and I have had several ex- periences of them — illustrate very forcibly how important the psychological factor is in the manage- ment of infants, and how carefully the motives of an infant's behaviour should be investigated by the analytical method. In this chapter I have attempted, I am afraid with conspicuous ill-success, to show how necessary it is to remember that, in dealing with infants, the general principles of physiology have applications no less important than in the case of older individuals. I have attempted to show that, as far as protein metabolism is concerned, the organic chemist has given us a lead which we should not be slow to follow. I have attempted also to show that the phenomena of immunity and anaphylaxis have their counterpart in various degrees of tolerance and intolerance, shown by different individuals for different kinds of food. I have also directed attention to the para- mount importance of suggestion in the instigation of otherwise inexplicable actions in infants. CHAPTER III Some Physiological Principles concerned in THE Determination of the Quantitative Food Requirements of Infants The quantity of food required by infants of different ages and of different weights has been determined not only by the direct calorimetric method, but also indirectly by the test-feed. The calorimeter method is based on the law of the conservation of energy ; that is to say, it is assumed that the energy expended in work, heat production, and other vital activities, is equivalent to the poten- tial energy of the food consumed. An infant confined in the chamber of a calorimeter is to aU intents and purposes an animal at rest. So that, although a considerable amount of energy is ex- pended in the internal work of the body — in carrying on the functions of respiration, circulation, and so on — practically the whole of it is finally converted into heat in overcoming friction or other resistances, and as such can be estimated by calorimetric methods. We can therefore make a theoretical calculation of the food requirements of the average baby by esti- 65 5 66 THE INFANT mating the average amount of heat lost by infants when confined in calorimeters, due allowance, of course, being made for the energy consumed in growth, or stored up in the form of food reserves. Calculations of this kind have in the past been repeatedly made by competent observers, and, although their results vary^ very considerably, they mostly appear to agree in the important respect that the heat dissipation — or, in other words, the food requirement — varies more or less directly with the extent of the skin surface of the baby, and not with the weight or age. Careful measurements of the superficies of infants of different weights have been made, and it is found that the skin area of a baby weighing 5 kilogrammes (11 pounds) measures 0*350 square metre (3 J square feet), while that of one weighing 10 kilogrammes (22 pounds) measures 0'555 square metre (5 J square feet), and that of a child weighing 40 kilogrammes (88 pounds) measures 1-4:42 metres (14 J square feet). Therefore the amount of heat lost by children of the respective weights of 5, 10, and 40 kilogrammes will stand in the proportion of 0350, 0-555, and 1-442, and not in the proportion of 5, 10, and 40, as might naturally be assumed. In accordance with these views, the reason why the dissipation of heat is supposed to be in proportion 1 Pfaundler and Schlossman, American edition, vol. i., p. 435 (second edition). QUANTITATIVE FOOD REQUIREMENTS 67 to the superficial area, and not to the weight, is because the heat is chiefly lost by radiation and conduction from the skin. As a matter of fact, under normal conditions some 60 per cent, of the total heat dissipated is lost by radiation and conduction, some 35 per cent, by evaporation of water at the surface of the skin and of the lungs, and the remain- ing 5 per cent, is lost in the urine or in other dis- charges from the body. Since some heat is lost by evaporation of water at the lungs' surface, it cannot be even theoretically true that the heat lost is pro- portional to the skin area. Now, since the quantity of food required by any particular infant is dependent on the amount of heat lost by radiation, conduction, and evaporation, and since the amount of this loss is itself chiefly dependent on the superficial area of the skin, it has been supposed to be quite easy, provided the amount of heat lost by any one given infant of known weight is known, to calculate from the known data the food requirements of any other infant situated under similar circumstances. From such simple data it has been estimated that during the first three months of life an infant requires enough food to supply 99 calories or units of heat for every kilogramme (2 pounds 3 ounces) of body- weight ; a calorie, or unit of heat, being that amount of heat which is required to raise 1 litre (35 ounces) of water through 1° of temperature (Centigrade). 68 THE INFANT For instance, an infant two and a half months old and weighing 5 kilogrammes (11 pounds) will require in the twenty-four hours enough food to produce 495 (99 x 5) calories. By a similar method of calculation it has been estimated that on an average during the next three months infants wiU require the equivalent of 94 calories per kilogramme (2 pounds 3 ounces) of b ody- weight ; or, to take a concrete example, an infant five months old and weighing 7 J kilogrammes (16J pounds) will require a food equivalent of 705 (94 x 7*5) calories. Again, on the same basis, it has been estimated that during the last quarter of the first year of life an infant will require a food equivalent of about 75 calories for every kilogramme (2 pounds 3 ounces) of body-weight. Now, how much milk will infants of different ages and different weights require to afford this theoretical number of calories ? The amount of heat or the number of calories afforded by the combustion of milk is not absolutely constant, because the chief heat-producing element in milk — namely, fat — is itself liable to variation, but on an average it may be assumed that 1 litre (35 ounces, or If pints) affords on combustion 700 calories. If a more accurate estimation of the caloric value of any particular milk, or milk mixture, is required, it may be made from the following data : 1 gramme (15 grains) of fat will produce 9-1 calories, 1 gramme QUANTITATIVE FOOD REQUIREMENTS 69 of sugar will produce 4-1^ calories, and 1 gramme of protein will also afford 4- 1 calories. On the basis of the above data it is quite easy to calculate how much milk of any particular per- centage composition babies of different ages wiU require. Let us take the simple example of an infant three months old weighing 5 kilogrammes (11 pounds). In twenty-four hours such a baby wiU dissipate 495 (99 x 5) calories in the twenty-four hours. How much milk will be required to afford this number of calories ? If 1 Utre (35 ounces) affords 700 calories, by quite a simple sum in proportion it may be shown that 495 calories are afforded by 700 c.c. (24i ounces). Theoretically, therefore, an infant of the above age and weight will require 700 c.c. of milk to compensate for the 495 calories of heat it is estimated to lose in the twenty-four hours by radiation, con- duction, and evaporation ; but it will also require a certain additional amount to provide for growth or increment in weight. On an average, a healthy infant of this age will show an increase in weight of nearly 30 grammes (1 ounce) during the twenty-four hours. How much milk will be required to afford material for this growth ? The proportion of solid constituents in the baby's 1 The caloric value of ordinary hydrous lactose is 3*78, while that of the anhydrous variety is 4-1. 70 THE INFANT body is rather more than twice as much as that in milk, exactly in the proportion of 28-2 to 12, so that assuming that the sohds of milk are of the same kind as those of the body, the baby must consume about 60 c.c. (2 ounces) of milk in the twenty -four hours to provide 30 grammes increment in body-weight. This, added to the 700 c.c. required for heat-produc- tion, will give a grand total of 760 c.c. (26J ounces) of milk in the twenty-four hours. Calculations such as these may have some value in giving us a general conception of the quantitative food requirements of infants, but if we rely too implicitly on them in calculating the dietary of any particular infant, we are quite certain to go widely astray. A baby in a calorimeter does not behave as a baby in the nursery ; it is situated under strange and unnatural conditions. Indeed, for the most part infants in calorimeters become restless and fretful, and cry continuously, thereby wasting much energy and dissipating a considerable number of units of heat by evaporation of moisture at the lungs' surface. And, further, we have no right to assume that under the equable conditions of tem- perature obtaining in the calorimeter the amount of heat lost by radiation and conduction is the same as that which is lost under the ever-varying con- ditions of a normal environment. Then, again, appetite, and consequently digestion and absorption, will be influenced by the strange QUANTITATIVE FOOD REQUIREMENTS 71 conditions, and a number of other complications will be introduced which must necessarily detract from the accuracy of the calorimeter results. With- out entering into further details, it is obvious that the conditions which determine food requirements in a calorimeter are not identical with those which determine food requirements in a nursery. The more recent work of Dr. P. Lavialle^ shows how important are considerations of clothing in esti- mating the amount of heat lost by radiation and conduction — in other words, how enormously an infant's food requirements are modified by its clothes. Dr. Lavialle, using a calorimeter of the D'Arsonval type, experimented with infants wearing different articles of clothing. Leaving the babies in the calorimeter for varying periods of time, he esti- mated the exact number of calories which were lost by radiation and conduction in accordance with the nature and character of the clothing worn. He found, for instance, that if an infant wore a simple bonnet which covered the parietal and occipital por- tions of the head, there was an actual saving in heat expenditure which was equivalent to 65 calories, or to the combustion value of GO c.c. (2 ounces) of milk. In other words, an infant wearing such a bonnet requires, ceteris "paribus, 2 ounces less milk in the twenty-four hours than an infant without 1 Congres National des Gouttes de Lait t6nu a Fecamp les 26, 27, et 28 Mai, 1912; Keport, p. 79. 72 THE INFANT such a covering to the head. Further, he estimated by the same method of experimentation that if the legs were protected by suitable stockings an economy of 220 c.c. (6 J ounces) was effected, and that the difference in heat expenditure when woollen and cotton shawls were used was represented by an equivalent 70 c.c. (2^ ounces) of milk. Such experiments prove how dangerous it is to attempt to apply theoretical principles to the prac- tical management of infants; it is so easy to leave important factors out of the calculation. There can be no doubt at all that the most important factor in an infant's requirements for food is the factor of heat dissipation. An infant at rest utilizes at least 80 per cent, of its food in maintaining its body temperature at the required level : unlike an adult, it diverts but httle energy into the channels of mechanical work; and, as we now know, although it grows rapidly, the amount of food required for this purpose is only equivalent to the intake in the twenty-four hours of some 60 grammes (2 ounces) of breast- milk. It therefore seems almost unac- countable that in the past the question of clothing and environmental temperature should have been taken so little into consideration. A few weeks ago I discussed these matters with a lady who takes a great interest in infant-welfare work. "It seems to me," she said, " that it would be of great interest to calculate how many garments a baby would have QUANTITATIVE FOOD REQUIREMENTS 73 to wear to enable it to do without any milk at all. I think some of our mothers must unconsciously be trying to solve this problem if we are to judge by the multipHcity of clothes they crowd on the bodies of their unfortunate infants." Such a reductio ad absurdum, if properly appreciated, emphasizes the important part that clothing plays in the feeding of infants. I feel sure that it is very necessary to draw atten- tion to this side of the question, for we have only to read the writings of even the greatest authorities on infant feeding to learn how largely this aspect of dietetics is neglected. Professor W. Camerer is probably one of the greatest authorities in the world on the food requirements of infants, but this is what he says in his otherwise most admirable article on " Metabohsm and Nutrition " in Pfaundler^ and Schlossman's textbook on The Disease of Children : " The influence of heat and cold can be nearly eliminated by means of clothing and dwelhngs." That is to say, Professor Camerer suggests that clothing and housing conditions do not aflect the question of food requirements, that in these respects all children are similarly situated, and that their different food requirements depend on other factors. I would, however, go so far as to say that in esti- mating the food requirements of any particular infant, the one important factor that we ought to 1 Second American edition, vol. i., p. 381. 74 THE INFANT take into account is that which is concerned with heat production. I do not mean by this that we must not take into consideration such matters as capacity to digest and assimilate food, habits, idiosyncrasies, and so on; all such factors are of great importance. What I mean is this — that, given two infants of equal ages and equal weights and growing at the same rate, and with normal digestive and assimilative functions, their respective food requirements, apart from the very small quantity required for growth and work, will be mainly dependent on the amount of heat that is lost by radiation, conduction, and evaporation of water. To put the case more concisely, I maintain that the different amounts of food these two infants will respectively require will be dependent on the number and thiclaiess of their clothes, on the amount of skin area (face, head, hands, feet, etc.) exposed to the air, on the temperature of the surroundings, on the degree of humidity of the air, on the ventilation, on the temperature of the bath, and on the number of hours spent in the open air, or in the confinement of the house, and that these factors may be entirely different in the two cases and necessitate totally different quantities of food. I repeat that it gravely misrepresents the case to state that " the influence of heat and cold is elimin- ated by the means of clothing and dwellings." I admit that the influence of " cold " is almost elimi- QUANTITATIVE FOOD REQUIREMENTS 75 nated in the case of the slum infant, who is wrapped in a multipHcity of garments, sleeps in its mother's arms or in her bed, and is seldom given a bath or taken out of doors ; but I submit that therein lies the difference between such an infant's food require- ments and that of an infant rationally managed with respect to clothing, housing, exercising, etc. In the one case there is no opportunity for heat dissipation, and hence there is an extremely restricted demand for heat production, and conse- quently for food, while in the other, although the demands may vary greatly with the circumstances, there is usually ample opportunity for loss of heat and always a corresponding demand for food. Although in the past I have myself been guilty of drawing up many a table of quantities for the feeding of infants of varying ages, I now fully admit that such tables are worthless unless other important considerations, such as those of clothing, housing, and airing, are simultaneously taken into considera- tion and allowances made for them. I have long held the view that these calorimeter results may be most misleading in determining how much food any particular baby requires. In the first place, an infant acquires certain " habits " of metabohsm as the result of its previous experiences in diet. For instance, one baby may be fed on 800 c.c. of breast-milk in the twenty-four hours, and another of the same weight and size may con- 70 THE INFANT sume a daily allowance of 1,600 c.c. Now, if the first baby is healthy and deals physiologically with its 800 c.c. of milk, it will show an output of half as many calories as the second baby, provided the latter also behaves in a similarly physiological manner. The first baby does not give out half as many calories as the second baby, because it only requires to produce this particular amount of heat to maintain a normal temperature under the par ticular conditions of the environment ; but because it must dissipate this particular number of calories in correspondence with the quantity of food digested and absorbed, or otherwise there would be a storing up of heat or of energy in some other form in the body, which, as Euclid says, " would be absurd." An infant accustomed to consume 1,600 c.c. of milk in the twenty-four hours acquires habits of rapid metabolism and active heat dissipation, which are very different from the sluggish habits acquired by the infant which consumes only half this quantity of milk. These habits become very inveterate, and make the subjects of them behave quite differently though the external conditions of the environment to which they may be respectively exposed are pre- cisely similar. These habits must be taken into consideration in determining dietaries. There can be no doubt that the actual quantities of food given to different infants do not. determine accurately the quantity of heat dissipated, for this QUANTITATIVE FOOD REQUIREMENTS 77 food may only in part be digested and absorbed; and although decomposition of food in the bowel may generate heat, the amount of heat thus pro- duced is not equivalent to the full caloric value of the food consumed. On the other hand, the external conditions wiU not evoke in different infants pre- cisely the same degree of combustion. Combustion and heat production must depend more on muscle activity and muscle tonus than on any other factor, although the factor of muscle tonus itself may depend on a vast number of afferent impressions reaching the central nervous system, and on the manner in which the nerve cell reflects these impres- sions and passes them on to the muscles. The whole question of muscular development and muscular tonus, and indeed voluntary and involuntary move- ments, must be very largely concerned in this question of heat production ; hence the unreUability of the calorimeter results in the sense in which they have been employed. The surface stimulation, by changing currents of air impinging on the skin of an infant, must clearly influence muscular tone and muscle metabohsm to a very large degree. The monothermic conditions of a calorimeter must deprive the infant of its normal share of such surface stimulation ; hence the findings of calorimeter experi- ments cannot be too exactly appHed to ordinary nursery conditions in which the ever changing events will excite the muscles to voluntary movements or 78 THE INFANT varying degrees of tonus. At the time of writing this I am not fully in possession of a number of inter- esting facts bearing on this subject, which Dr. Fritz Talbot, of Boston, tells me are undergoing investi- gation at the Carnegie Institution in Washington. The second method of estimating the quantitative food requirements of infants — namely, the empirical one of calculating the average amount of milk consumed by healthy infants at the breast — has provided us with a large amount of data for drawing up standards for the artificial feeding of infants; but I submit that deductions drawn from these findings are themselves as liable to misconstruction and misrepresentation as are the results of the more scientific calorimetric method. The amount of food consumed by breast-fed infants has been estimated by the method to which some years ago I ventured to apply the term " test- feed"; that is to say, the infant is weighed on accurate scales before and after feeding; the differ- ence between the two weighings represents the amount of food consumed. By making a number of such estimations, or by estimating the amount consumed at each feeding, certain averages have been arrived at, which are supposed to represent the average requirements of normal infants, and these figures have been indiscriminately applied to the case of all infants no matter what be the circum- stances of the hygienic surroundings. QUANTITATIVE FOOD REQUIREMENTS 79 Now, the point that I wish to make perfectly plain is that the observations on which we rely have been made on infants living under the very best hygienic condition. Some of them have been the observer's own children, while some of them have been infants born and tended in public maternity institutions, where every care and attention have been lavished on the mother, and the standards thus arrived at have been supposed to be applicable to the case of the slum infant, who may be living under the worst possible conditions of housing, ventilation and general hygiene. A considerable number of figures have been pro- vided by such means, and on the whole I find the standards thus estimated agree very closely with the standards I have myself formed from estimating the amount of breast-milk consumed by the infants of well-to-do mothers in England. On the other hand, until a series of observations were undertaken to show the amount of breast-milk consumed by the average slum infant, there was no criterion whereby to judge how much food such infants com- monly consume. It was taken for granted that they obtained as much milk as the better-con- ditioned infants on whom observations had actually been made. During the last eight years I have made a practice of giving each breast-fed infant who is brought to my clinics a test-feed, or perhaps many test-feeds. 80 THE INFANT In this way I have accumulated an enormous amount of evidence on the subject. It is true that I have not been able to make an estimation of all the feeds given in the twenty-four hours in any one particular case. I have had to content myseH with estimating the average amount consumed in the twenty-four hours by multiplying the amount consumed at one feed by the number of feeds taken in the whole day ; but all the same, I have now made so many estimations at different hours of the morning, afternoon, and evening that I feel sure that my averages for single feedings, and conse- quently for the twenty-four hours, are fairly accur- ate. In estimating the total amount taken in the twenty-four hours from the amoimt taken at a single feed, one must allow for the total number of feeds and for the fact that the largest feed in the day is usually the first feed in the morning after both mother and infant have enjoyed a long rest. Further, one must make some allowance for the fact that in the strange environment of a dispensary or a hospital an infant will not attend to the business of sucking quite as well as in the home. But making allowance for all such sources of error, I find that the average consumption of breast-milk by the slum infant is about 33 per cent, less than the estimates given by German observers for institute infants, or than the estimates I have myself made in the case of infants in well-to-do families. QUANTITATIVE FOOD REQUIREMENTS 81 An examination of the following tables will show how widely my figures differ from the standards arrived at by foreign observers ; it will further show how closely my own estimates agree with the figures independently arrived at by Dr. Ronald Carter, who carried out a similar series of experiments on the infants attending at his infant consultations in North Kensington. In the first horizontal column I give my own figures, w^hich refer to test-feeds conducted in the case of slum infants attending at my infant con- sultations in Marylebone. In the second column I give those of Dr. Carter, which apply to a similar class of infant attending at his infant consultations in North Kensington. In the third column I give my own figures for sick infants attending at my out- patient department at the Queen's Hospital for Children, Hackney, a very poor district in the north- east of London. In the remaining columns will be found the figures supplied by German observers. These refer for the most part to institutional infants, or to private cases in a good position of life. My figures, as well as those of Dr. Carter, are based on a very large number of observations, whereas those of the German observers depend sometimes on a single observation, sometimes on small groups of cases, but in no case on a large number of estimations. If we compare this series of figures, we notice at once that the amount of breast-milk consumed by 6 CO .t^ CO 00 (M o • • CO (M GO o r-H t- isJOO CO o o CO .o ^CO (M QO i-H CO VO N C0 »0 lO -4^ "^ -^ lo '^ (>i r^ C^iOCOCOTfiO •^ _»0 lO NOi 00 t- t^ lO ■^ 00 lo t- lo o rH cq CO ■ lO C -M ^-, .O O 1 1 ""^ CO lO O CO o o o o < ^00(M COIOOO O T)< OlO CO rH O !>• GO CD r-H r-H l-H CO (N (M (N (MO O lO lO O O ^- o lo CO (N c-q lo o CO OcOtJ* tJ< 00 CD 00 00 ,-H l-H r-H C<| G0 000 5-1 Oi:DO OOOOt-t-r-^CO r-i(N i-HC>iO ooooo a eci 04< <:6 |oiO00I>C^ l-H rH ' C anyone in this country." LECTURES ON DISEASES OF CHILDREN. Third Edition, revised and greatly enlarged. About 400 pages, with many new Illustrations. Demy 8vo., cloth. los. 6d. net. " The whole of the book has been revised, and may be commended as a safe and convenient guide to the practitioner."— Zrt«c^2'. , i • . j ttooT, ^f tV.f"cP additions ^ " In the second revised edition fresh chapters have been inserted. Each of these additions enhances the value and usefulness of the work. Dr. Hutchison P^f.^^^. J^^^^^^P^ §f °f,J.^^^^^ the main essentials of each complaint in a plain and lucid manner. -British Medical J ou7 nat. 6 From Mr. Edward Arnold's List Practical Anatomy. The Student's Dissecting Manual. By F. G. Parsons, F.R.C.S. Eng., Lecturer on Anatomy at St. Thomas's Hospital and at the London School of Medicine for Women ; Examiner for the Fellowship of the Royal College of Surgeons of England, etc. ; and William Wright, M.B. , D.Sc, F.R.C.S. Eng., Lecturer on Anatomy at the London Hospital ; Examiner at the Royal College of Surgeons of England, and at the Universities of London and Bristol, etc. In Two Volumes. With many Illustrations. Large crown 8vo. Price per volume, 8s. 6d. net. Human Embryology and Morphology. By Arthur Keith, M.D. Aberd., F.R.C.S. Eng., Conservator of the Royal College of Surgeons. Third Edition. Revised and Enlarged, with many new Illustrations. Demy 8vo., cloth. 15s, net. A Manual of Pharmacology. By Walter E. Dixon, M.A. , M.D., B.Sc. Lond., D.P.H. Camb., Professor of Materia Medica and Pathology, King's College, London ; Examiner in Pharma- cology in the Universities of Cambridge and Glasgow. Third Edition, thoroughly revised. Demy Svo. 15s. net. Practical Physiology. By M. S. Pembrey, M.A., M.D. ; A. P. Beddard, M.A., M.D. ; J. S. Edkins, M.A., M.B. ; Martin Flack, M.A.; M.D. , Leonard Hill, M.B., F.R.S. ; J. J. R. MACLEOD, M.B. Illustrated by numerous diagrams and tracings. Third Edition, revised and enlarged. xviii-f48o pages. Demy 8vo. 14s. net. Applied Physiology. By Robert Hutchison, M.D. Edin., F.R.C.P. , Physician to the London Hospital and to the Hospital for Sick Children, Great Ormond Street. 7s. 6d. net. Further Advances in Physiology. Edited by Prof. Leonard Hill. With contributions by Experts in various branches. 448 pages. 15s. net. Old Age : its Care and Treatment in Health and Disease. By Robert Saundby, M.D. Edin.; F.R.C.P. Lond.; Pro- fessor of Medicine in the University of Birmingham ; Consulting Physcian to the General Hospital, Birmingham, to the Birmingham and Midland Counties Eye Hospital, and to the West Bromwich Hospital. vii + 312 pages. 7s, 6d. net. Military Hygiene and Sanitation. By Col. C. H. Melville, M.B. Edin., D.P.H., R.A.M.C, Professor of Hygiene, Royal Army Medical College. 418 pages. 12s. 6d. net. The Sanitary Officer's Handbook of Practical Hygiene. By Major C. F. Wanhill, R.A.M.C, Assistant Professor of Hygiene, Royal Army Medical College; and Major W. W. O. Beveridge, D.S.O., R.A.M.C, Analyst to the Army Medical Advisory Board. Interleaved with blank pages for notes. New and Revised Edition. Crown Svo. 6s. net. Forensic Medicine and Toxicology. By C. O. Hawthorne, M.D., Lecturer on Forensic ISIedicine, London School of Medicine for Women, etc. Third Edition, entirely re-written and greatly enlarged. vii + 344 pages. Crown 8vo., cloth. Cs.net. OF Medical Books Malingering and Feigned Sickness. By Sir John Collie, M.D., J. P., Medical Examiner, London County Council; Chief Medical Officer, Metropolitan Water Board ; Medical Examiner to the Shipping Federation, Sun Insurance Office, Central Insurance Company, London, Liverpool, and Globe Insurance Company, and other Accident Offices. Second Impression. Demy 8vo. los. 6d. net. Modern Theories of Diet, and their Bearing upon Practical Dietetics. By A. Bryce, M.D., D.P.H. Camb. xvi+368 pages. 7s. 6d. net. Glycosuria and Allied Conditions. By P. J. Cammidge, M.D. Lond., D.P.H. Camb. Demy 8vo., cloth. i6s. net. The Treatment of Diseases of the Skin. By W. K. Sibley, M.A., M.D., B.C. Camb., M.R.C.P. Lond., M.R.C.S. Eng., Physician to St. John's Hospital for Diseases of the Skin, London, viii+280 pages. With Illustrations from Original Photographs. 5s. net. Electro - Therapeutics for Practitioners. Being Essays on some useful forms of electrical apparatus, and on some diseases which are amenable to electrical treatment. By Francis Howard HuMPHRis, M.D. Brux., F.R.C.P. Edin., M.R.C.S. Eng., President of the American Electro Therapeutic Association. Svo., cloth. Illustrated. 8s. 6d. net. Tabular Diagnosis. An Aid to Rapid Differential Diagnosis of Disease. By Ralph Winningtox Leftwich, M.D., late Assistant Physician to the East London Children's Hospital. 7s. 6d. net. A Pocket-Book of Treatment. By Ralph Win- ningtox Leftwich, M.D. viii + 34S pages. Flexible binding, with wallet flap. New and Revised Edition. 6s. net. Contributions to Abdominal Surgery. By Harold Leslie Barnard, M.S., F.R.C.S., Late Assistant Surgeon, London Hospital. xix+ 391 pages. Illustrated. 15s. net. Fractures and Separated Epiphyses. By A. J. Walton, M.S., F.R.C.S., L.R.C.P., Surgical Registrar, London Hospital. 312 pages. 100 Illustrations. los. 6d. net. The House-Surgeon's Vade-Mecum. By Russell Howard, M.B., M.S., F.R.C.S., Surgeon to the Poplar Hospital; Assistant Surgeon to the London Hospital. With 142 Illustrations. viii + 516 pages. 7s. 6d. net. Surgery for Dental Students. By G. Percival Mills, M.B., B.S. Lond., F.R.C.S. Eng., Surgeon to the Royal Orthopaedic and Spinal Hospital, Birmingham ; and H. Humphreys, M.B., Ch.B., B.D.S. Birm., L.D.S. Eng., Demonstrator in Dental Surgery at the Dental Hospital, Birmingham. Illustrated. 12s. 6d. net. 8 From Mr. Edward Arnold's List INTERNATIONAL MEDICAL MONOGRAPHS. General Editors: Leonard Hill, M.B., F.R.S., Lecturer on Physiolop:y, London Hospital Medical School ; and William IBullgch, M.D., Bacterio- logist and Lecturer on Bacteriology and General Pathology, London Hospital. In this series will be found volumes dealing with subjects of exceptional interest and importance, giving in a concise form the results of the leading investigators in special branches of medical science throughout the world. Attention also is given to the practical application of the results of scientific research to the treatment of disease. The Mechanical Factors of Digestion. By Walter B. Cannon. A.M., M.D., George Higgmson Professor of Physiology, Harvard University. xii + 227 pages. Cloth, Illustrated. los, 6d. net. Syphilis : A Systematic Account of Syphilis from the Modern Standpoint. By James McIntosh, M.D. Aberd., Grocers' Research Scholar; and Paul Fildes, M.B., B.C. Camb., Assistant to the Bacteriologist of the London Hospital, xvi + 228 pages. Illustrated with 8 Full-page Plates and 5 Diagrams, cloth. los. 6d. net. Blood-Vessel Surgery and its AppHcations. By Charles Claude Guthrie, M.D., Ph.D., Professor of Physiology and Pharmacology, University of Pittsburgh, etc. xii + 350 pages. 158 Illus- trations, cloth. 14s, net. Caisson Disease and Diver's Palsy : The Ilhiess of Workers in Compressed Air. By Leonard Hill, M.B., F.R.S. , Lecturer on Physiology, London Hospital. xi+255 pages. Illustrated, cloth, los. 6d. net. Lead Poisoning and Lead Absorption : The Symptoms, Pathology and Prevention, with Special Reference to their Industrial Origin and an Account of the Principal Processes Involving Risk. By Thomas M. Legge, M.D. Oxon., D.P.H. Cantab., H.M. Medical Inspector of Factories ; Lecturer on Factory Hygiene, University of Manchester; and Kenneth W. Goadby. D.P.H. Cantab., Pathologist and Lecturer on Bacteriology, National Dental Hospital, viii + 308 pages. Illustrated, cloth. 12s. 6d. net. The Protein Element in Nutrition. By Major D. McCay, M.B., B.Ch., B.A.O., M.R.C.P. Lond., I.M.S., Professor of Physiology, Medical College, Calcutta. xv + 2i6pages. Illustrated, cloth, los. 6d. net. The Carrier Problem in Infectious Disease. By J. C. G. Ledingham, M.B., D.Sc, Chief Bacteriologist, Lister Institute of Preventive Medicine, London ; and J. A. Arkwright, Assistant Bacteriologist, Lister Institute of Preventive Medicine, London, vii + 319 pages. Cloth. 12s 6d. net. Diabetes : Its Pathological Physiology. By John J. R. MACLEOD, M.B.. Ch.B., D.P.H., Professor of Physiology, Western Reserve University, Cleveland, O., U.S.A., late Demonstrator of Phy- siology, London Hospital. Illustrated. los. 6d. net. LONDON : EDWARD ARNOLD, 41 6^ 43 MADDOX STREET, W. UNIVEESITY OF CALIFOENIA LIBEAEY, BEEKELEY THIS BOOK IS DUE ON THE LAST DATE STAMPED BELOW Books not returned on time are subject to a fine of 50c per volume after the third day overdue, increasing to $1.00 perS^olume after the sixth day. Books not in demand may be renewed if application is made before expiration of loan period. WiM U.C. BERKELEY LIBRARIES CD3T7mbT3 401205 UNIVERSITY OF CALIFORNIA LIBRARY LUUUlliUl!lJLtLL'.Uillt!UUL!IllllLMin!H!f''"!!'l''*V*'''' '••'''' ^