HOLMES.
ANALYSIS OF THE CIRCULATION
| 1. Its Composition. | 1. THE BLOOD | 2. Its Uses. | | 3. Transfusion. | |4. Coagulation | | | 1. Description. | | 2. Movements. | | 3. Auricles and Ventricles. | | | | 1. The | | a. Need of. | | Heart.| | b. Tricuspid and | | | | Bicuspid. | | | 4. The | c. The Strengthen- | | | Valves. | ing of the | | | | Valves. | | | | d. Semilunar | | | | Valves. | | _ | 2. ORGANS OF THE | 2. The | 1. Description. | CIRCULATION | Arteries | 2. The Arterial System. | | |_3. The Pulse. | | _ | | 3. The | 1. General Description. | | Veins |_2. Valves. | | _ | | 4. The | 1. Description. | | Capilla-| 2. Use. | |_ ries |_3. Under the Microscope. | _ | | 1. The Lesser. | 3. THE CIRCULATION.| 2. The Greater. | |3. The Velocity of the Blood. | | 4. THE HEAT OF THE | 1. Distribution. | BODY. |2. Regulation. | | 5. LIFE BY DEATH. | | 6. CHANGE OF OUR BODIES. | | 7. THE THREE VITAL ORGANS. | | 8. WONDERS OF THE HEART. | | | 1. Description | 9. THE LYMPHATIC | 2. The Glands. | CIRCULATION. | 3. The Lymph. | |4. The Office of the Lymphatics. | | | 1. Congestion. | | 2. Inflammation. | | 3. Bleeding. | 10. DISEASES. | 4. Scrofula. | | 5. A Cold. | |6. Catarrh. | | | 1. Effect of Alcohol upon the Circulation. | 11. ALCOHOLIC | 2. Effect of Alcohol upon the Heart. | DRINKS AND | 3. Effect of Alcohol upon the Membrane. |_ NARCOTICS. | 4. Effect of Alcohol upon the Blood. |_5. Effect of Alcohol upon the Lungs.
THE CIRCULATION.
THE ORGANS OF THE CIRCULATION are the heart, the arteries, the veins, and the capillaries.
FIG. 35.
[Illustration: A, corpuscles of human blood, highly magnified; B, corpuscles in the blood of an animal (a non mammal).]
THE BLOOD is the liquid by means of which the circulation is effected. It permeates every part of the body, except the cuticle, nails, hair, etc. The average quantity in each person is about eighteen pounds. [Footnote: It is difficult to estimate the exact amount, and therefore authorities disagree. Foster places it at about one thirteenth of the body weight.] It is composed of a thin, colorless liquid, the plasma, filled with red disks or cells, [Footnote: There is also one white globular cell to every three or four hundred red ones. The blood is no more red than the water of a stream would be if you were to fill it with little red fishes. Suppose the fishes to be very, very small—as small as a grain of sand— and closely crowded together through the whole depth of the stream; the water would look quite red, would it not? And this is the way in which, blood looks red—only observe one thing; a grain of sand is a mountain in comparison with the little red fishes in the blood. If I were to tell you they measured about 1/3500 of an inch in diameter, you would not be much wiser; so I prefer saying (by way of giving you a more perfect idea of their minuteness) that there would be about a million in such a drop of blood as would hang on the point of a needle. I say so on the authority of a scientific microscopist—M. Bouillet. Not that he has ever counted them, as you may suppose, any more than I have done; but this is as near an approach as can be made by calculation to the size of 1/3500 part of an inch in diameter.—JEAN MACE.] so small that about three thousand five hundred placed side by side would measure only an inch, and it would take sixteen thousand laid flatwise upon one another to make a column of that height. Under the microscope, they are found to be rounded at the edge and concave on both sides. [Footnote: By pricking the end of the finger with a needle, we can obtain a drop for examination. Place it on the slide, cover with a glass, and put it at once under the microscope. The red disks will be seen to group themselves in rows, while the white disks will seem to draw apart, and to be constantly changing their form. After a gradual evaporation, the crystals (Fig. 36) may be seen. In animals, they have various, though distinctive forms.] They have a tendency to collect in piles like rolls of coin. The size and shape vary in the blood of different animals. [Footnote: Authorities differ greatly in their estimate of the size of the disks (corpuscles) in human blood. The fact is that the size varies in different persons, probably also in the same individual. Many of the best microscopists therefore hesitate to state whether a particular specimen of blood belonged to a human being or to an animal. Others claim that they can distinguish with accuracy. Evidently, the question is one of great uncertainty. The following statement of the size of the cells in different animals is taken from Gulliver's tables: Cat, 1/4404 of an inch in diameter; whale, 1/3100; mouse, 1/3614; hog, 1/4230; camel, 1/3123; sheep, 1/3352; horse, 1/4800; Virginia deer, 1/5038; dog- faced baboon, 1/4861; brown baboon, 1/3493; red monkey, 1/3396; black monkey, 1/3530.] Disks are continually forming in the blood, and are constantly dying—twenty million at every breath.—DRAPER.
The plasma also contains fibrin, [Footnote: it is usual to say that fibrin is contained in the blood. It probably does not exist as such, but there are present in the blood certain substances known as paraglobulin and fibrinogen, which by the action of a third substance, fibrin ferment under certain circumstances, form fibrin and so cause coagulation. The exact nature of the process by which fibrin is produced by these three factors is not understood—See Foster's Text Book of Physiology, p 22.] albumin—which is found nearly pure in the white of an egg—and various mineral substances, as iron, [Footnote: Enough iron has been found in the ashes of a burned body to form a mourning ring.] lime, magnesia, phosphorus, potash, etc.