19. Ganglionic corpuscles are chiefly found in the cerebro-spinal axis; in the ganglia of the posterior nerve roots, and in those of the sympathetic; but they occur also elsewhere, notably in some of the sensory organs (see Lesson IX.). They are spheroidal bodies, consisting of a soft semisolid cell substance in the midst of which is a large FIG. 103-PAPILLE OF THE SKIN OF THE FINger. a, a large papilla containing a tactile corpuscle (e) with its nerve (d): b, other papillæ, without corpuscles, but containing loops of vessels, c. (Magnified about 300 diameters.) clear and transparent area usually termed the nucleus. Within the nucleus again is generally a smaller body commonly termed the nucleolus (Fig. 102, D, a). Each ganglionic corpuscle sends off one, two, or more prolongations, which may divide and subdivide; and which, in some cases, unite with the prolongations of other ganglionic corpuscles, while, in others, they are continued into nerve-fibres. A TABLE OF ANATOMICAL AND PHYSIOLOGICAL THE weight of the body of a full-grown man may be taken at 154 lbs. Skin Fat APPENDIX A. I. GENERAL STATISTICS. Such a body would be made up of— Or of CONSTANTS. Thoracic viscera Water. Solid matters The addition of 7 lbs. of blood, the quantity which will readily drain away from the body, will bring the total to 154 lbs. A considerable quantity of blood will, however, always remain in the capillaries and small bloodvessels, and must be reckoned with the various tissues. The total quantity of blood in the body is now calculated at about 1-13th of the body weight, i.e. about 12 lbs. The solids would consist of the elements oxygen, hydrogen, carbon, nitrogen, phosphorus, sulphur, silicon, chlorine, fluorine, potassium, sodium, calcium (lithium), magnesium, iron (manganese copper, lead), and may be arranged under the heads of— Proteids. Amyloids. Fats. Minerals. Such a body would lose in 24 hours-of water, about 40,000 grains, or 6 lbs. ; of other matters about 14,500 grains, or over 2 lbs. ; among which of carbon 4,000 grains; of nitrogen 300 grains; of mineral matters 400 grains; and would part, per diem, with as much heat as would raise 8,700 lbs. of water o° to 1° Fahr., which is equivalent to 3,000 foot-tons. Such a body ought to do as much work as is equal to 450 foot-tons. The losses would occur through various organs, thus—by Creditor--Solid dry food Oxygen Total Debtor-Water. OTHER Other Matters grs. 12,000 1,000 700 800 14,500 N. grs. ... 250 IO 40 The gains and losses of the body would be as follows : grs. 8,000 10,000 36,500 300 C. grs. 3,300 140 100 460 4,000 54,500 grs. 40,Coo 14,500 Total 54,500 A foot-ton is the equivalent of the work required to lift one ton one foot high. Proteids II. DIGESTION. Such a body would require for daily food, carbon 4,coo grains, nitrogen 300 grains; which, with the other necessary elements, would be most conveniently disposed in Minerals. 400 36,500 Total 44,500 which, in turn, might be obtained, for instance, by means of Lean beefsteaks Milk Potatoes Butter, dripping, &c. grs. 2,000 4,400 1,200 grs. 5,000 6,000 7,000 3,000 600 22,900 Total 44,500 The fæces passed, per diem, would amount to about 2,800 grains, containing solid matter 800 grains. III. CIRCULATION. In such a body the heart would beat 75 times a minute, and probably drive out, at each stroke from each ventricle, from 5 to 6 cubic inches, or about 1,500 grains of blood. The blood would probably move in the great arteries at a rate of about 12 inches in a second, in the capillaries at I to 1 inches in a minute; and the time taken up in performing the entire circuit would probably be about 30 seconds. The left ventricle would probably exert a pressure on the aorta equal to the pressure on the square inch of a column of blood about 9 feet in height; or of a column of mercury about 9 inches in height; and would do in 24 hours an amount of work equivalent to about 90 foot-tons; the work of the whole heart being about 120 foot-tons. IV. RESPIRATION. Such a body would breathe 15 times a minute. The lungs would contain of residual air about 100 cubic inches, of supplemental or reserve air about 100 cubic inches, of tidal air 20 to 30 cubic inches, and of complemental air 100 cubic inches. The vital capacity of the chest-that is, the greatest quantity of air which could be inspired or expired—would be about 230 cubic inches. There would pass through the lungs, per diem, about 350 cubic feet of air. In passing through the lungs, the air would lose from 4 to 6 per cent. of its volume of oxygen, and gain 4 to 5 per cent. of carbonic acid. During 24 hours there would be consumed about 10,000 grains oxygen; and produced about 12,000 grains carbonic acid, corresponding to 3,300 grains carbon. During the same time about 5,000 grains or 9 oz. of water would be exhaled by the lungs. In 24 hours such a body would vitiate 1750 cubic feet of pure air to the extent of 1 per cent., or 17,500 cubic feet of pure air to the extent of 1 per 1,000. Taking the amount of carbonic acid in the atmosphere at 3 parts, and in expired air at 470 parts in 10,000, such a body would require a supply per diem of more than 23,000 cubic feet of ordinary air, in order that the surrounding atmosphere might not contain more than 1 per 1,000 of carbonic acid (when air is vitiated from animal sources with carbonic acid to more than 1 per 1,000, the concomitant impurities become appreciable to the nose). A man of the weight mentioned (11 stone) ought, therefore, to have at least 800 cubic feet of well-ventilated space. V. CUTANEOUS EXCRETION. Such a body would throw off by the skin-of water about 18 ounces, or 10,000 grains; of solid matters about 300 grains; of carbonic acid about 400 grains, in 24 hours. |
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