The Project Gutenberg EBook of Obesity, or Excessive Corpulence: The Various Causes and the Rational Means of Cure, by François Dancel This eBook is for the use of anyone anywhere in the United States and most other parts of the world at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org. If you are not located in the United States, you'll have to check the laws of the country where you are located before using this ebook. Title: Obesity, or Excessive Corpulence: The Various Causes and the Rational Means of Cure Author: François Dancel Editor: Michael Barrett Translator: Michael Barrett Release Date: April 29, 2018 [EBook #57069] Language: English Character set encoding: ISO-8859-1 *** START OF THIS PROJECT GUTENBERG EBOOK OBESITY, OR EXCESSIVE CORPULENCE *** Produced by Carlos Colón, The University of Alberta and the Online Distributed Proofreading Team at http://www.pgdp.net (This file was produced from images generously made available by The Internet Archive) Transcriber's Notes: Blank pages have been eliminated. Variations in spelling and hyphenation have been left as in the original. A few typographical errors have been corrected. The cover page was created by the transcriber and can be considered public domain. OBESITY, OR EXCESSIVE CORPULENCE: THE VARIOUS CAUSES and THE RATIONAL MEANS OF CURE. From the French of Dancel. TRANSLATED AND EDITED BY M. BARRETT, M.A., M.D. TORONTO: W. C. CHEWETT & CO., KING STREET EAST. 1864. PRINTED BY W. C. CHEWETT & CO., KING STREET EAST, TORONTO. PREFACE. The subject of "Obesity," including its cause and treatment, has received during the past few years a great deal of attention both in England and on the Continent. Thousands of persons have realized the extraordinary benefit to be derived from the simple treatment laid down in the following pages. Some members of the medical profession have, in the course of their practice, availed themselves of the theory first propounded by our Author, but have failed to acknowledge—either through ignorance or inadvertence—the source of their information. Under these circumstances it has been deemed an act of justice, though tardy, to place before the profession and the public a translation of the original work of Dancel, modifications in matters of theory have, however, been introduced, which the progress of science imperatively demanded. The invariable success which has attended the treatment of several cases of obesity in this city, in accordance with the principles established by Dancel, warrants the assertion that the system is in every respect worthy of public confidence. AUTHOR'S PREFACE. To the many individuals of both sexes who are afflicted with an excessive development of fat, rendering the ordinary duties of life not only irksome but ofttimes impossible,—an easy method of reducing obesity, in nowise interfering with the ordinary daily avocations of the patient, nor demanding any diminution in the actual amount of food consumed; requiring the use of none but the mildest and most harmless medicinal agents; improving at the same time the general health, and augmenting bodily and mental vigour,—must prove acceptable. The process will be found not a mere speculative theory, but one based upon the great laws of Nature, as manifested throughout the whole of the animal kingdom. AUTHOR'S PREFACE to the THIRD EDITION. Can corpulence be reduced without injuriously affecting the general health? This is the grand question, and it is suggestive of another, which is:—an inordinate amount of fat once having been deposited in and among the living tissues, is its presence necessary for the preservation of the health and life of the individual? My answer is,—most assuredly no! Every one knows that an undue degree of corpulence is not only accompanied with great inconvenience to the individual, but is, in most instances productive of ill health, and too frequently of positive disease. Having answered this question, another occurs:—are there any substances generally known to the profession which have the power either to destroy fat or to cause its disappearance, and which, at the same time, will have no action upon the other tissues of the body? My reply is most assuredly there are such; and I will prove my assertion in this respect to be correct, without resorting to the use of subtle reasonings or invoking the aid of learned theories, but will be content to rest it upon the sure foundation of chemical science,—on that science which teaches the action of one body with another, which shews us that in some cases no change whatever is effected by the mechanical combination of two or more indifferent substances; and that in other instances, the chemical union of two bodies will be productive of a third, having properties wholly dissimilar from either of the two original substances:—thus, that one or more elementary substances or chemical compounds may enter into combination with a fatty body to produce a third, and yet have no power of action whatsoever upon the muscles, the bones, the nerves, or any other than the fatty tissues of the living organism. Knowing, therefore, the chemical constituents of fat, and also those entering into the composition of the several articles of diet which are principally made use of in the civilized world, we are enabled to say of a certain class of alimentary substances, that such contain the elementary ingredients of fat; and that if you desire to escape the inconveniences and evils attendant on corpulency, it will be well to abstain from them; and that, on the other hand, by making use of such and such alimentary substances, and that too in any quantity the appetite may prompt, there will be no danger of suffering the inconveniences alluded to, because such substances contain but a minute portion of those elements which enter into the composition of fat. In the following treatise, a system for the reduction of corpulence, based upon the above well-recognized truths, will be found fully developed, and its correctness established by means of numerous cases brought forward, in which the results have been entirely satisfactory, and where the patients have kindly permitted me to state their names and addresses. [viii] [ix] [x] CONTENTS. PAGE Translator's Preface iii. Author's Preface v. Author's Preface to Third Edition vii. CHAPTER I. Introduction 1 CHAPTER II. Sterility 7 Virility 8 CHAPTER III. Hernia 9 Umbilical Hernia 10 Medical Theories 14 Medical Specialism 16 Periodic Headache 17 Effect of loss of blood 18 Apoplexy 19 Sanguineous Apoplex 20 Pulmonary Affections 21 Fatty Liver 22 Abdominal Dropsy 23 Hepatic Obstruction 24 Broussais, his Theory 25 Signs of Hepatic Obstruction 27 Uterine Affections 28 Skin Disease 29 Cause of Obesity 30 Hysteria 31 Sudden Death 32 CHAPTER IV. Quantity of Fat 35 Case in Java 36 [xii] Appearance of the Obese 37 Pallor 38 Varicose Veins 40 Somnolence 41 Effects of Exercise 43 Pre-disposition to Fat 44 Intestinal Tract 46 Composition of Fat 47 Chemistry of Fat 48 Experimental Feeding 50 Effects of Fluids 51 Nitrogenous Food 52 Carnivora 53 Hippopotamus 54 Whale Tribe 55 Insufficient Exercise 56 Active Exercise 57 Jail Prisoners 58 Carbon of Plants 59 CHAPTER V. Treatment of Obesity 60 Delarding 61 Compulsory Abstinence 62 Use of Acids 63 Use of Iodine 64 Similarity of Fat and Water 65 Alkalis 66 Bi-Carbonate of Soda 67 Alkalis alone not sufficient 68 Increased Tone 69 CHAPTER VI. Cases of Reduction of Corpulence 70 Case of Guénaud 71 Increased Muscular Power 73 Unimpeded Respiration 74 Diet 75 [xiii] Case of Widow Rollin 76 Case of Chauvin 77 Case of Roberts 78 Swelling of the Legs 79 Palpitation 80 Cardiac Symptoms 81 No excess of Blood 82 Case of Madame Meuriot 83 Case of Madame Pecquet 86 Loss of One Hundred Pounds weight 88 Case of Madame de M. 89 Case of Lucian Eté 92 Case of Madame d'Hervilly 93 Case of M. Desbouillons 94 Systematic Opposition 96 Trembley 97 Not a matter of Faith 98 Fat and Fatigue 99 Case of Madame C. 100 Change of Temperament 101 Case of Albert C. 102 Case of Mr. L. 103 Case of Dr. Halberg 105 Case of Jules Wimy 107 The Postmaster at Orleans 109 Constancy of Result 110 Resolution necessary 111 The Fat Professor 113 Cases of Skin Disease 114 Prejudices Overcome 115 CHAPTER VII. On the selection of alimentary substances favorable to the reduction of Corpulence 116 Man Omnivorous 117 Power of Selection 118 Of Meats 119 Of Fish 120 [xiv] Of Milk 121 CHAPTER VIII. Of Beverage 122 Beer and Cider 123 Alcoholic Drinks 124 Wine and Water 125 Of Tea and Coffee 126 Strong Coffee 127 OBESITY; OR, EXCESSIVE CORPULENCE. CHAPTER I. INTRODUCTION. The physician has a twofold duty to perform. He is called upon not merely to alleviate pain, and to undertake the cure of disease, but he is, moreover, required to lay down rules for the preservation of health, the prevention of disease, and its too frequent concomitant, pain. Now, health being dependent upon the due and regular performance of the vital functions by the several physiological organs of the body, any excessive development of these organs, or undue manifestation of force on their part, must, of necessity, be contrary to the general health of the body, and be productive of disease and pain. In many persons there exists a constitutional tendency to the excessive formation of blood, occasioning a plethoric condition, and thereby rendering the individual liable to a great many diseases; others again suffer from an exalted or diminished sensibility of the nervous system, inducing some of the greatest woes to which humanity is liable. Many different elements are combined in the structure of the various organs of the body, and among these fat, in suitable proportion, must be recognized as necessary for the due and equable performance of the several organic functions. This fat, however, often becomes excessive, giving rise at first to great inconvenience, after a time inducing debility, and finally constituting a disease (hitherto deemed incurable) termed obesity. The possession of a graceful figure may be of little importance, in so far as the happiness of most men is concerned; but as regards the gentler sex, such is by no means the case. Women are too apt to believe that, in the absence of physical beauty, the possession of mental and worldly treasures can only suffice to render them endurable in their social relations. Beauty, the richest gift of nature, deserves to be carefully guarded by those who happily possess it; corpulence, its enemy, is destructive to the finest organization. It is a painful sight to witness the many instances of women, who, though still of youthful years, and whose elegance of form, but a short time since, did but enhance their unsurpassed loveliness of countenance, lose by degrees, in the midst of an overwhelming fat, all this relative and graceful harmony, and whose ever increasing corpulence serves only to render them ill-favoured and repulsive. In all cases, so detrimental a change is much to be regretted; but for ladies mingling in the fashionable spheres of life, it is to be borne only when such a condition can be shewn to be utterly beyond all hope of relief. Excessive corpulence has destroyed the prospects of many, both men and women, by rendering them incompetent to discharge the duties of a profession by which they had hitherto gained an honourable livelihood. Superabundance of fat prevents an infantry officer from following his regiment—a cavalry officer from being long on horseback; and thus both are alike compelled to retire from the service. The operatic artiste, whose voice or personal beauty had been hitherto a mine of wealth to the theatre, falls into indigence, because an excessive development of fat now embarrasses the lungs or destroys her personal charms. Every one engaged in intellectual pursuits will say that since he has increased in fat he finds that he cannot work so easily as he did when he was thin. The painter feels the want of that vivid imagination which was wont to guide his brush. The sculptor labours with indifference upon the marble. The literary man feels heavy, and his ideas no longer flow in obedience to his will. The clerk in his office is ever complaining of the efforts he is obliged to make to resist an overwhelming drowsiness which interferes with his calculating powers, rendering him unable to compose a letter, or even to copy one. Obesity, in fact, lessens both physical and moral activity, and unfits man for the ordinary business of life. It was in conformity with this opinion, no doubt, that the Romans at one time, wishing to have no drones among them, banished those of their fellow citizens who laboured under an excessive development of fat. One can conceive of the existence of such a law among a people who condemned to a like punishment any citizen known to be indifferent to the public welfare. We must admit, however, that it would be a grave error to assert that all persons suffering under an excess of fat are invariably wanting in the finer feelings, or even in moral energy. There are many living proofs to the contrary. But it is among women chiefly that we witness instances of great mental refinement and susceptibility, in union with a body steadily increasing to a lamentable size. Moralists have written that obesity is a sign of egotism; of a good stomach, but of a bad heart; and many may be found [1] [2] [3] [4] [5] to endorse the sentiment. Unhappily people are easily dazzled with high sounding words, and the sententious phrases of moralists. This is wrong; for if we take the trouble to adopt for a moment the opposite to that which they advance, we shall often find that this opposite is not void of reason. In support of this remark many reasons can be advanced why a fat person should have a good heart, and be endowed with most excellent qualities. Corpulence, it is true, usually indicates good digestive powers; but good digestion is not incompatible with goodness of heart. One who digests his food easily ought to be better disposed towards those around him, than the sickly creature labouring under dyspepsia. What amount of temper can be expected in those who daily experience pain in the stomach while the digestive process is going on? they can have no joyousness of heart, but must continually be in bad humour, too often seen in their contracted and jaundiced features. It is a great mental effort on their part to receive you with even a seeming cordiality. We may always accost a person with a degree of confidence, whose skin is gracefully spread over a sufficient layer of fat. I may be mistaken, but in my opinion we need not expect to meet in such persons great mental anxiety, or intense egotistical feelings. Julius Cæsar was warned a few days before his assassination that an attempt would be made upon his life:—Antonius and Dolabella were accused of being the conspirators. "I have but little dread of those two men," said he, "they are too fat, and pay too much attention to their toilette; I should rather fear Brutus and Cassius, who are meagre and pale- faced." The end justified Cæsar's opinion. With respect to lean persons, I shall not undertake to oppose the general opinion that a delicate organization is emblematic of a mind endowed with a great member of most precious and good qualities, frequently used with such energy, as by its very strength to be the cause of bodily weakness. But let us beware of entering the domain of Lavater, Gall and Spurzheim. We would rather say that the emblem of health is a sufficient but not too great rotundity of person —mens sana in corpore sano. [6] CHAPTER II. Sterility must be numbered among the infirmities induced by excessive corpulence. This is a well attested fact in reference to the human species, and also as to the females of the lower animals. One of the professors in the Medical Faculty of Paris, while explaining in his lectures how fat could interfere with conception, never failed to cite the practice of the peasantry, who hastened to send to market those hens which became excessively fat, because they then ceased to lay eggs. Even plants lose their fertility by excess of fat. A plant growing in a cultivated soil where it finds a superabundance of food becomes sterile, because the stamens are transformed into petals, causing double flowers. The rule is, in order that a woman should be capable of conception, that she should be regular—that is to say, that she should lose each month a certain quantity of blood. Now it is asserted by medical men that, in general, those women who are thin, and who are almost without exception fertile, lose much more blood than fat women. Menstruation lasts with them from five to ten days, whilst fat women lose but very little blood during two or three days at the most. It may be added that in the first of these three days the loss is considerable, the second day there is scarcely any, and on the third day there is more, but it then ceases. Just in proportion as a thin woman becomes fat, her menstrual flow diminishes, and so much the more speedily, the quicker she becomes fat. Some women who have thus increased in fat have ceased to menstruate at thirty-five, at twenty-five, and even at twenty years of age. Some young girls, regular at twelve or fourteen years of age, on becoming fat, have ceased to menstruate and become chlorotic. One great result of the anti-obesic treatment is, that while destroying the excessive amount of fat, it causes women to become regular, and thus favours conception. Thin men in general possess greater virility than those surcharged with fat, and in proportion as this fat is developed virility is impaired and finally lost. This infirmity happens to many corpulent men at fifty, forty-five and even forty years of age. Some who were very very fat at the age of puberty, have been impotent throughout life. There are facts which prove that virility in man, like fertility in woman, may be restored on losing a superabundance of fat. [7] [8] CHAPTER III. The human skin is capable of great extension. It may be distended to four times its size, yet is not endowed with much elasticity. On this account we may notice, in very fat persons, rolls of fat about the neck, back, buttocks, arms and pubis. The epidermis, which constitutes the external layer of the skin, is but slightly capable of extension. When distended beyond a certain point, it tears, and produces those white streaks which are to be seen on the abdomen of pregnant women, or of those who have borne children, and also of those who have laboured under severe dropsical ascites. These white streaks may be formed upon all parts of the body, when the skin is considerably distended: thus they have been seen in a young woman twenty-eight years of age, who weighed three hundred and four pounds. In her case these white streaks were to be seen upon the arms, the shoulders, the breasts, &c. The skin of the abdomen would not be sufficient to retain the abdominal viscera in situ, were it not that between these organs and the integument there exists a fibrous or muscular layer, in some places double, consisting of a stronger and less extensible tissue than the skin, in order to strengthen the abdominal walls. It sometimes happens that this fleshy layer, having yielded to a certain amount of distension, occasioned by the volume of the intestines, and of their surrounding fat, and being thereby unduly stretched, permits the passing between its fibres of a certain portion of intestine or of fat, which, lying immediately under and pushing the skin before it, constitutes what is termed a hernia. Dropsy or pregnancy are frequently the primary cause of the various descriptions of hernia, termed inguinal, crural, &c. Umbilical hernia is that which is usually produced by a too great development of fatty tissue in the abdomen. The umbilicus is that part of the abdomen which is the least susceptible of dilatation. When the belly becomes enlarged to a moderate extent, the navel becomes depressed, shewing that this part does not easily yield to the pressure from within; but it is supported by the recti muscles, those two bands of fleshy fibres lying immediately beneath the skin, and passing from above downwards, on each side and close to the navel. In extreme development of the abdomen, these muscles are displaced from their normal position near the umbilicus, and no longer lend it support. The fibres of the umbilical ring are thus separated by the pressure exerted by the abdominal fat, and a portion passing through the fibres pushes the skin before it. A small protrusion takes place, which is not yet outwardly apparent, because the remaining fibres of the umbilical ring still afford considerable resistance, and retain the ring concealed in the deep hollow which is observable in the navel of fat persons. In order to determine the existence of umbilical hernia at this early stage, the patient should be placed in the recumbent position. On introducing the little finger into the navel depression, and directing the patient to cough, we feel an impulse against the finger which is not to be felt, under the same circumstances, over any other portion of the abdominal walls. In some cases of hernia it is not absolutely necessary to place the person in the recumbent position, but in this case it is indispensable: unless we do so the impulse cannot be felt, since it cannot take place in the upright position. In the year 1851, a lady consulted me. She was then very fat, and the abdomen was greatly enlarged. I said to her, "You have probably umbilical hernia." "I have long feared that such was the case," she replied, "but happily I have not. Only a few days ago my own physician examined me, and he declared that I had not. He has advised me to wear an abdominal supporter." Noticing her great enlargement, I was not satisfied of the non-existence of hernia. I begged to be allowed an examination. Having obtained her consent, I immediately detected, by the means I have previously pointed out, a small hernia in the depth of the navel cavity. She had great confidence in her own physician, and told me positively that I was mistaken. I recommended her to see her own physician, and to be examined again by him in the same manner as I had examined her. There was no doubt in my mind but that he would detect it, and such was the case; but he said that it had occurred since his previous examination: possibly so. An umbilical truss was immediately adapted; for it is only in hernia at its early stage that we can hope for a cure by means of a truss, and by removing the cause, that is to say, by reducing the mass of fat existing in the abdomen. If the development of a small hernia is not prevented, it gradually increases, and makes its appearance upon the walls of the abdomen. At first it is of the size of a small pear, a hen's egg; afterwards it increases to six, eight, ten, fifteen or twenty pounds weight. It then assumes more or less the shape of a mushroom, which is exceedingly troublesome, as it requires to be supported by means of a hollow truss, a species of box with springs. Umbilical hernia is to be met in more than one half the number of persons who measure fifty-five inches round the abdomen. Such is the progress of medical science, that the following ideas as to the diseases which may be engendered by excessive corpulence, would have been deemed, twenty-five years ago, unworthy of a doctor of medicine: a hundred and fifty years ago they would have obtained the applause of the physicians of those days. At the present time I foresee —I am indeed sure, that the medical profession will acknowledge these same ideas to be founded upon reason and observation, two indispensable requisites in all that concerns the healing art. When the system of medicine founded by Borelli was in vogue, called the "Iatro Mathematical," it would certainly have been acknowledged that a superabundance of fat, when developed in the human body, could interfere with the vital organs in the performance of their functions, and thus be the cause of much disturbance and of many diseases. But this would no longer have been admitted, when Broussais, the distinguished author of "Chronic Phlegmasia," in our own day, in harsh and severe language, and with an air of conviction, loudly proclaimed that all disease resulted from local irritation, whence it was irradiated throughout the organism, as in the case when a sharp instrument pierces the flesh. This theory was the very opposite to the teachings of the majority of medical men of a previous age, who maintained [9] [10] [11] [12] [13] [14] that local disease resulted from a general disturbance of the whole system. Thus, if the stomach were affected, Broussais called the disease a gastritis (or inflammation of the stomach), which might induce disturbance of the system at large; while many of the old school would have said that if the stomach were especially diseased, it was because nature chose that channel in order to eliminate from the body the morbid principle which in the outset had attacked the entire system. It belongs not to the subject on hand to endeavour to signalize all the errors of the old school, nor to set forth what truth there may be in the system; but I would ask one simple question. It has happened to every medical practitioner to be called in to see a person recently taken ill, and that he has said, "The disease is not yet well characterized; by-and-bye, or to-morrow, I shall be able to form an opinion, and say what the disease is." But until this "by-and-bye," until this "to- morrow," what happens to the patient? for it is evident that there is sickness, a general ailment. And when one particular portion of the body, an organ, is principally affected, when the disease has there manifested itself, as we say, shall we be far wrong in saying that it is a kind of crisis? It would be just what happens, only more evidently, in those fevers which terminate in a critical abscess. Nor is it advisable that I should speak of the founder of physiological medicine. His vast labours are the result of great genius, and have long influenced the medical world with all the weight of a master mind. Having been his pupil for many years, I shall never cease to admire his life of scientific labour. Nevertheless, I cannot refrain from remarking how much he has done to lessen the spirit of medical enquiry. By localizing all diseases, and by his system of irritation, without taking into account the constitution as a whole, how greatly is the labour of the physician reduced! how little knowledge is necessary on his part to be deemed worthy of the title of Doctor of Medicine! Once upon the highway of localization, once engaged in this contracted study, there is no stop. It is no longer necessary to be acquainted with all the organs, both in a state of health and of disease; the extent of territory to be explored is reduced. The fashion at the present day is, that a physician of this school should know only how to treat the diseases of one particular organ, and rarely of two; that he should be, in fact, a specialist. But are not the principal organs of the body, for the most part, mutually dependent on each other, and all of them subject to a general consensus? What is the consequence of this medical specialism? Why, that every physician so engaged thinks, and most conscientiously, that the patient before him labours under that particular disease to which he particularly devotes his attention. This is perfectly natural. The mind of man is so formed, that it is narrowed, and loses its powers of comparison and of judgment, whenever it is concentrated and brought to bear solely upon one subject, one single object. Man is no longer capable of reasoning upon a science or an art, when he puts it out of sight as a whole, in order to devote himself entirely to one of its parts; but ends by making the subject of his study the principal point, the all-important one, whence flow, in his opinion, all the rest; and finally assumes that a part is equal to the whole. When a patient complains of palpitation of the heart, he prescribes a bleeding, leeches, digitalis. If another complain of sense of weight or oppression, bleedings, softening syrups, troches, &c., are prescribed. If another complain of headache, dizziness, with threatening apoplexy, he is bled. Everything is treated locally, without inquiring whether the evil be or be not the effect of some general cause. Among a vast number of general causes, giving rise to disease, I purpose to treat of one, and that is excessive corpulence, termed obesity. In our recent medical works, no reference is made to this morbid predisposition, in regard to the diseases occasioned by it. I do not mean to say that superabundance of fat is the cause of all the ills that flesh is heir to; but I am persuaded and do affirm that it is often the primary cause of many diseases. Thus, in cases of headache, there are assuredly many which are produced by superabundance of fat, because they commenced when that superabundance began to appear, and ceased on its being diminished. Frequent headache, becoming periodic, is constantly met with in fat people. Nothing is more common among such persons than dizziness. In these cases, are not the blood-vessels oppressed with fat interfering with a free circulation of the blood, and is not fat therefore the cause of all these troubles? But it may be said that the blood produces these affections, since, after loss of blood, the patients are relieved. I do not agree with this, and I say that the blood is not in such cases the cause of these ailments; because fat people, both men and women, have no more blood than thin persons: I maintain that they have even less. It is granted that loss of blood in cases of headache, vertigo, alleviate and even cure these affections; but only for a time; for eight days, or a month or two at the most, and then gradually reappear, and bleeding is again required. This amelioration, these momentary cures, produced by blood-letting, are to be explained in such cases by saying that the quantity of blood, although not so great in fat as in thin people, is impeded in its circulation, and that loss of blood, by still further diminishing the quantity, facilitates for a while its passage through the blood-vessels. This method is consequently only palliative; it does not attack the root of the evil. Bleeding takes away blood which is troublesome only in consequence of the excess of fat; for every physician is aware that repeated bleedings tend to the development of fat in an extraordinary degree. Fat people insist upon being bled at more frequently recurring periods, because their corpulence continues to increase, and headaches and dizziness become more frequent. The seemingly useful remedy increases the cause of the trouble. Notwithstanding the temporary relief, and apparent cure, corpulence finally produces such a disturbance of the brain, or of some other vital organ, as suddenly to produce death in the course of an hour or two, with every appearance of excess of health. Usually an attack of serous or sanguineous apoplexy is the cause of death in persons labouring under [15] [16] [17] [18] [19]