have been detected. In a case of pericarditis, in which the author felt great interest, the pulse exhibited a decided intermission every few beats, yet the heart beat its due number of times; the intermission of the pulse at the wrist consisting in the loss of one of the beats of the heart. It was not improbable but that in this case the contractility of the aorta was unusually developed by the inflammatory condition of the heart; and that the flow of blood from the ventricle was thus occasionally spasmodically diminished or entirely impeded. The quickest pulse, which Dr. Elliotson' ever felt, was 208, counted easily, he says, at the heart; though not at the wrist. The pulse of the adult female is usually from ten to fourteen beats in a minute quicker than that of the male. In infancy, it is generally irregular, intermitting, and always rapid, and it gradually becomes slower in the progress of age. It is, of course, impossible to arrive at any accurate estimate of its comparative frequency at different periods of life, but the average of the following numbers, on the authority of Heberden, Sömmering, and Müller,3 may, on the whole, be regarded as approximations. Dr. Guy lays down the following as a near approximation to the average numbers at the several leading periods of life. It must be borne in mind, that, as in all similar cases, such averages can never apply to special examples. Researches by MM. Hourmann and Dechambre," do not accord with these estimates in respect to the smaller number of pulsations in the aged. MM. Leuret and Mitivié had suspected an error in this matter from an examination of 71 of the aged inmates of the Bicêtre and La Salpêtrière. MM. Hourmann and Dechambre examined 255 women 1 Human Physiology, p. 215, London, 1840. 2 Med. Transact., ii. 21. 3 Handbuch der Physiologie, Baly's translation, p. 171, London, 1838. between the ages of 60 and 96, and found the average number of the pulse to be 82.29. M. Rochoux,' however, still believes-from the results of his own observations as well as those of others-that, as a general rule, the frequency of the pulse diminishes in the progress of age. The attention of Dr. Pennock,2 of Philadelphia, has more recently been directed to the subject; and the author has great confidence in the authenticity of results recorded by him. In 170 males, and 203 females, of the average age of about 67, the average frequency of the pulse was 75. The difference between the pulse of the male and female continues to be well marked in advanced life. MM. Leuret and Mitivié found the average frequency in 27 aged men, 73; and in 34 aged women, 79. The average obtained by Dr. Pennock was 72 for the former; 78 for the latter. Dr. Gorham3 assigns 130 as the mean number of the pulse from five months to two years old; and 107.63 from two to four years of age, whence the number continues almost the same up to the tenth year. His estimates, however, are much higher than those of M. Valleix. M. Trousseau,' from repeated observations, infers, that but little stress ought to be laid on the pulse in the diagnosis of disease in infants. He found, that during the first two weeks, it may vary from 78 to 150; during the second fortnight, from 120 to 164; from one to two months, from 96 to 132; two to six months, 100 to 162; six to twelve months, 100 to 160; and from twelve to twenty-one months, 96 to 140. From the observations of MM. Billard, Valleix, and others, it would seem, that the pulse of the foetus at the moment it is expelled from the uterus often falls to 83 in the minute, and, in some minutes afterwards, rises to 160. In the course of the first day, it falls again to 127, and continues to diminish during the first ten days, the average being then from 87 to 90. These are, however, only averages: the variations are very great. Sex appeared to have some influence. In infants, from eight days to six months old, the average number of pulsations for boys was 131; for girls, 134; from six to twenty-one months, the average for boys was 113; for girls, 126. The state of sleeping or waking had a greater influence. In infants from fifteen days to six months old, the average of the pulse was 140 during waking; 121 during sleep. He has known it rise from 112 to 160 and 180, when the child cried or struggled. On the whole, M. Trousseau concludes, that the pulse of children at the breast varies from 100 to 150. After the first two months, it is a little more frequent in females than in males; and is about 20 higher in the waking than in the sleeping state. Strange to say, it may be wholly absent, without the health seeming to be interfered with. A case of the kind is referred to by Prof. S. Jackson, as having occurred in the mother of a physician of Philadel 6 Art. Pulse, in Dict. de Méd., 2d edit., xxv. 619, Paris, 1842. 2 Amer. Journ. of the Medical Sciences, July, 1847, p. 68. 3 Lond. Med. Gaz., Nov. 25, 1837. 4 Mémoires de la Société Médicale d'Observation de Paris, tom. ii., Paris, 1844. Journ. des Connaiss. Méd. Chir., Juillet & Août, 1841; cited in Amer. Journ. Med. Sciences, Oct., 1841, p. 458, and Jan., 1842, p. 199. The Principles of Medicine, founded on the Structure and Functions of the Animal Organism, p. 492, Philad., 1832. A case of complete disappearance of the beating of the heart phia. The pulse disappeared during an attack of acute rheumatism, and could never again be observed. Yet she was active in body and mind, and possessed unusual health. In no part of the body could a pulse be detected. Dr. Jackson attended her during a part of her last illness-inflammation of the intestines; no pulse existed. She died whilst he was absent from the city, and no examination of the body was made. Between the number of pulsations and respirations there would not appear to be any fixed relation. In many persons the ratio in health is 4 to 1,' but in disease it varies greatly. Dr. Elliotson alludes to a case of nervous disease in a female at the time in no danger whose respiration was 106, and pulse 104. Dr. Knox3 has made some observations on the pulsations of the heart, and on its diurnal revolution and excitability, from which he infers: 1. The velocity of the heart's action is in a direct ratio with the age of the individual,—being quickest in young persons, slowest in the aged. There may be exceptions to this, but they do not affect the general law. 2. There are no data to determine the question of an average pulse for all ages. 3. There is a morning acceleration and an evening retardation in the number of the pulsations independently of any stimulation by food, &c. 4. The excitability of the heart undergoes a daily revolution;-that is, food and exercise affect its action. most in the morning and during the forenoon; less in the afternoon, and least of all in the evening. Hence it might be inferred, that the pernicious use of spirituous liquors must be greatly aggravated in those who drink before dinner. 5. Sleep does not farther affect the heart's action than through the cessation of all voluntary motion, and a recumbent position. 6. In weak persons, muscular action excites that of the heart more powerfully than in the strong and healthy; but this does not apply to other stimulants, wine and spirituous liquors, for example. 7. The effect of the position of the body in increasing or diminishing the number of pulsations is solely attributable to the muscular exertion required to maintain the body in the sitting or erect posture; the debility may be measured by altering the position of the person from a recumbent to a sitting or erect one. 8. The most pow erful stimulant to the heart's action is muscular exertion. The febrile pulse never equals this." h. Uses of the Circulation. The chief uses of the circulation are,-to transmit to the lungs the products of absorption, in order that they may be converted into arterial blood; and to convey to the different organs arterial blood, which is in Gazette Médicale, Nov. 21, 1836; and analogous cases are given in Parry on the Pulse, Bath, 1816, and in Medico-Chirurg. Review, xix. 285, and April, 1836. Quetelet, Sur L'Homme, p. 87; also, Guy, Pennock, &c., in Art. Pulse, op. cit., and Dr. John Reid, art. Respiration, ibid., pt. xxxii. p. 338, Lond., 1848. 2 Human Physiology, p. 215, Lond., 1835. See, also, Dr. Ch. Hooker, of New Haven, Conn., in Boston Medical and Surgical Journal, for May 16, 23, &c., 1838. 3 Edinburgh Medical and Surgical Journal, April, 1837. 4 The article on the Pulse, by Dr. Guy, in Cyclop. of Anat. and Physiology, is an excellent resumé of the whole subject. is not only necessary for their vitality, but is the fluid by which the different processes of nutrition, calorification, and secretion are effected. These functions will engage us next. We may remark, in conclusion, that the agency of the blood, as the cause of health or disease, has had greater importance assigned to it than it merits; and that although the blood may be the medium, by which the source of disease is conveyed to other organs, we cannot look to it as the seat of those taints that are commonly referred to it. "Upon the whole," says Dr. Good,1 "we cannot but regard the blood as, in many respects, the most important fluid of the animal machine; from it all the solids are derived and nourished, and all the other fluids are secreted; and it is hence the basis or common pabulum of every part. And as it is the source of general health, so is it also of general disease. In inflammation, it takes a considerable share, and evinces a peculiar appearance. The miasms of fevers and exanthems are harmless to every part of the system, and only become mischievous when they reach the blood; and emetic tartar, when introduced into the jugular vein, will vomit in one or two minutes, although it might require perhaps half an hour if thrown into the stomach, and in fact it does not vomit till it has reached the circulation. And the same is true of opium, jalap, and most of the poisons, animal, mineral, and vegetable. If imperfectly elaborated, or with a disproportion of some of its constituent principles to the rest, the whole system partakes of the evil, and a dysthesis or morbid habit is the certain consequence; whence tabes, atrophy, scurvy, and various species of gangrene. And if it becomes once impregnated with a peculiar taint, it is wonderful to remark the tenacity with which it retains it, though often in a state of dormancy and inactivity for years, or even entire generations. For as every germ and fibre of every other part is formed and regenerated from the blood, there is no other part of the system that we can so well look to as the seat of such taints, or the predisposing cause of the disorders I am now alluding to; often corporeal, as gout, struma, phthisis: sometimes mental, as madness; and occasionally both, as cretinism." This picture is largely overdrawn. Setting aside the erroneous. pathological notions that assign to the blood what properly belongs to cell life in the system of nutrition, how can we suppose a taint to continue for years, or even entire generations, in a fluid which is perpetually undergoing mutation; and, at any distant interval, cannot be presumed to have one of its quondam particles remaining? Were all hereditary diseases derived from the mother, we could better comprehend this doctrine of taints; inasmuch as, during the whole of foetal existence, she transmits the pabulum for the support of her offspring: the child is, however, equally liable to receive the taint from the father, who supplies no pabulum, but merely a secretion from the blood at a fecundating copulation, and from that moment can exert no influence. on the character of the progeny. The impulse to this or that organization or conformation must be given from the moment of union of the particles, furnished by each parent at a fecundating intercourse; and 1 Op. cit. it is probable, that no material influence is exerted subsequently even by the mother, except through the pabulum she furnishes. The embryo accomplishes its own construction, as independently of the parents as the chick in ovo. i. Transfusion and Infusion. The operation of Transfusion,-as well as of Infusion of medicinal agents, was referred to in an early part of this chapter, to prove the course of the circulation to be from the arteries into the veins. Both these operations were suggested by the discovery of Harvey. The former, more especially, was looked upon as a means of curing all diseases, and of renovating the aged ad libitum. The cause of every disease and decay was presumed to reside in the blood, and, consequently, all that was necessary was to remove the faulty fluid, and substitute pure blood obtained from a healthy animal in its place. As a therapeutical agency, the history of this operation does not belong to physiology. The detail of the fluctuation of opinions regarding it, and its total disuse, are given at some length in the Histories of Medicine, to which we must refer the reader. It appears to have been first performed on man in France by Denis and Emmerez in 1666; and in the following year it was practised in England by Drs. Lower and King. Before this, however, many experiments had been made on animals. In his "Diary" under the date of the 14th of November, 1666, Pepys3 has the following entry:-"Dr. Croone told me, that at the meeting of Gresham College to-night, which, it seems, they now have every Wednesday again, there was a pretty experiment of the blood of one dog let out, till he died, into the body of another on one side, while all his own run out on the other side. The first died upon the place, and the other very well, and likely to do well. This did give occasion to many pretty wishes, as of the blood of a Quaker to be let into an Archbishop, and such like; but, as Dr. Croone says, may, if it takes, be of mighty use to man's health, for the amending of bad blood by borrowing from a better body." There are some interesting physiological facts, connected with transfusion, that cannot be passed over. MM. Prévost and Dumas found that the vivifying power of the blood does not reside so much in the serum as in the red particles. An animal bled to syncope was not revived by the injection of water or of pure serum at a proper temperature; but if blood of one of the same species was used, the animal seemed to acquire fresh life, at every stroke of the piston, and was at length restored. 4 The operation was revived by Dr. Blundell, and by MM. Prévost and Dumas; the first of whom employed it with safety, and he thinks with happy effects, in exhausting uterine hemorrhage. All these gen 1 Sprengel, K., Histoire de Médecine, par Jourdan, iv. 120, Paris, 1815. 2 J. P. Kay, art. Transfusion, Cyclopædia of Practical Medicine, Amer. edit., by the author, iv., 468, Philad., 1845; and The Physiology, &c. of Asphyxia, p. 254, Lond., 1834. 3 Diary and Correspondence of Samuel Pepys, F. R. S., by Lord Braybrooke, 3d edit., iii. 336, London, 1848. 4 Médico-Chirurgical Transactions, ix. 56; and x. 296; and Researches physiological and pathological, p. 63, London, 1825. Bibliothèque Universelle, xvii. 215. |