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9. But suppose that good wholesome chyme has passed the doorway of the pylorus, what is the next step in the process? We are looking to see how blood is made from the food we have eaten. First, then, through a little channel the liver pours upon the chyme a quantity of that bitter yellow fluid called bile; then another organ, called the pancreas, pours upon it the pancreatic juice; some other juices are also poured in, and these liquids convert a portion of the chyme into a thin whitish fluid called chyle.*
10. As this chyle is carried along in the intestine it comes in contact with the mouths of numerous little veins, and also the mouths of numerous little hair-like tubes called lacteals,5 both of which absorb it, and convey it to what is called the thoracic duct; and this duct empties it into a large vein, which conveys it to the heart. After this it is sent to the lungs, where it is acted upon by the oxygen of the atmosphere, as we shall hereafter describe, when it becomes blood -a stock of fresh materials, suitable to aid in repairing, building up, and nourishing the body.
"For this the watchful appetite was given,
The chyle to blood; the foamy purple tide
12. But what does this blood, which circulates in our bodies, consist of? The blood of man consists of a colorless liquid, composed mostly of water, in which are seen floating a great number of very small, flat, circular atoms, or sacs, called disks or cells, a few of them white, but most of them red. If twelve thousand of these thin, flat cells were placed one upon another, they would make a pile of less than an inch in thickness! These cells seem to be a kind of living atoms, for
* Oils and fats are not digested in the stomach, but only after they have passed into the intestine, and been acted upon by the bile. They are then absorbed by the lacteals. Although we speak of the mouths of the lacteals, they are so small as to be invisible even by the aid of glasses, and may be considered as mere pores leading to those tubes.
they have their periods of birth, of growth, of decay, and of death; and they are nourished by the liquid in which they float. Countless myriads of them come into existence every day; and it is said that at every pulsation of the heart nearly twenty millions of them die. Has not physiology, then, its passing wonders, as well as astronomy? (See Fig. 8.)
13. While the blood, as a whole, has its own peculiar labors to perform in nourishing the body and removing its waste particles, each part of the blood has its separate duty. Thus the liquid in which the blood-cells float carries along the nourishing materials which are dissolved in it; but the business of the cells is to carry the oxygen. They take it in at the lungs, carry it where it is needed to burn up the waste particles of carbon and convert them into carbonic acid gas, and then go back for a new supply. What a wonderful process this is! But when the cells get old, and worn out in this labor, they shrivel up with age, they lose their bright crimson color, and assume a tawny hue like the decaying leaves of autumn, and at length they die-millions of them at every breath we draw. Some portions of their dead remains are used in repairs of the system, while other portions are strained off in the liver, and used for the manufacture of bile.
14. The relative position of the principal organs of the body, and the manner in which they are neatly packed to
Fig. 8 represents a very small drop of human blood, containing the circular blood-cells magnified 500 diameters. As the blood-cells in other animals are not similar in size and shape to those found in man, the microscope will detect the difference.
gether, may be seen in the drawing, Fig. 9, which we have given below. In the drawing Fig. 10 is a separate representation of the principal organs of digestion, which are engaged in manufacturing that life-bearing and life-preserving current, the blood, from the food we have eaten. He who made them, He who planned this curious manufactory, has assigned to them their duties; and faithfully will they keep laboring on in our service through a long life, if we furnish them the proper materials to work with, and guard them
EXPLANATION.-Fig. 9: c the windpipe. Back of the heart it branches to both lungs. B, B, the right and left lungs; A, the heart; d, the diaphragm, the muscle separating the chest from the abdomen; D, the stomach; S, the spleen (or milt), supposed by the ancients to be the seat of melancholy. Its use is not well determined. C, the liver, the largest organ in the body; 1, the gall-bladder, on the under surface of the liver; m, m, the two kidneys, the right one the lowest; V, situation of the pylorus; O, the pancreas; w, w, the small intestine, sometimes called the second stomach; f, f, f, the colon, or large intestine.
Fig. 10: 3, the a-soph'-a-gus, through which the food passes into the stomach; 13, cardiac orifice of the stomach; 14, splenic extremity; 15, pyloric extremity; 18, pylorus; 19, 20, 21, that part of the small intestine called the du-o-de'-num; 22, gall-bladder; 23, cystic duct; 24, hepatic duct; 25, common gall duct; 26, its opening into the du-o-de'num; 27, duct of the pancreas opening into the du-o-de'-num; 28 to 30, that part of the small intestine called the je-ju'-num; 30 to 31, that part called the il'-e-um, 31, opening of the il'-e-um into the large intestine, or co'-lon; 36, 37, 38, 39, the colon; 40, rectum.
from danger, and from the many abuses to which they are liable from our ignorance, our folly, and our neglect.
15. But oh! how sadly are these faithful servants often abused by us! How often do we give the stomach more labor than it can perform'! How often do we fill it with crude and indigestible materials, until it rebels against our tyranny, or sinks exhausted in our service! How often do many poison it with vile drinks'! How often do they neglect to give it the repose which it needs! How generally are its laws of healthy action violated'! And the sad consequences are they not evident all around us, in thousands of cases of suffering, disease, and early death'?
SA-LI'-VA; when discharged from the 6 THO-RAC'-IC (tho-ras'-ik); the thoracic mouth it is called spittle. duct is the great trunk of the absorbent
? SU-PER-A-BUND'-ANCE, more than enough.
3 IR-RI-TA-TING, causing unhealthy action. 7 AL-I-MENT, food; nutriment. PĂN'-CRE-AS, a gland that pours out a 8 PUL-SA'-TION, the beating or throbbing of kind of saliva. the heart. LAO'-TE-ALS, these are slender hair-like 9 CRUDE, unripe; raw. tubes.
THE BEST COSMETICS.
1. YE who would save your features florid,
Adopt this plan
"Twill make, in climate cold or torrid,
2. Avoid, in youth, luxurious diet;
Be wisely gay;
So shall ye, spite of Age's fiat,
3. Seek not, in Mammon's worship, pleasure;
In books, friends, music, polished leisure:
Made the sole scale by which to measure
4. This is the solace, this the science,
But challenges, with calm defiance,
ABUSES OF THE DIGESTIVE ORGANS.-LAWS OF THEIR HEALTHY ACTION.
1. We have seen not only that the bones and muscles are formed from the blood, and kept in repair by it, but that the blood itself is formed, by the labors of the digestive organs, out of the food provided for them. It will readily be seen, moreover, that the healthy action of these organs in manufacturing the blood must depend upon several conditions, such as the proper quantity and quality of the food supplied for them to work upon, the times and manner of the supply, and the condition of the system1 when food is taken.
2. Without a suitable quantity of food, there will not be a sufficient quantity of blood to build up the body, and keep it in repair. When the body is growing rapidly, as in youth, more food is required as building material than when the period of youth has ended. This accounts for the keen appetite and vigorous digestion in childhood. For a similar reason, when the body has become emaciated by disease, or want of nutriment, an increased supply is needed to repair the waste.
3. It has been seen that muscular exertion increases the flow of blood, for the purpose of repairing the waste that always attends action. Hence those accustomed to hard labor require a greater supply of food than those of inactive habits