The heart is in front, between the two tubes of the lungs. It is likewise wedge-shaped, the base, or larger end being up, while the small end points downward, slanting into the left chest; it occupies one-third more room in the left chest than in the right, measuring from the centre of the breast bone, under which the heart is placed, towards the middle of the breast bone.
This important organ is little known, and I wish to explain its offices and revolutions, in a comprehensive manner, that all may understand it.
We have three different kinds of blood vessels; the largest vein is called vena cavæ; the smaller veins are called capillaries and arteries; every time you prick yourself, you open a capillary vein. On the right side is the vena cavæ, one part descending and the other ascending, but both meeting on the right side; this brings all the contaminated blood from all parts of the body; from thence it empties into the right ventricle, then to the right auricle, pushes on to the pulmonary artery, through the lungs, to be purified, returns with velocity to the left auricle, and then to the left ventricle. There are thousands and tens of thousands little arteries, that carry the blood to all parts of the body.
I will quote a report from Dr. Edwards. He had been speaking of the wonderful distribution of the blood, in the little arteries, when he added:
“Along on the lines of these little tubes or canals, (the arteries,) through which the blood with all its treasures flows, God has provided a vast multitude of little organs, or waiters, whose office is each one to take out of the blood, as it comes along, that kind and quantity of nourishment which it needs, for its own support, and also for the support of that part of the body which is committed particularly to its care. And, although exceedingly minute and delicate, they are endowed by their Creator with the wonderful power of doing this, and also of abstaining from, or of expelling and throwing back into the common mass, what is unsuitable, or what they do not want, to be carried to some other place where it may be needed; or, if it is not needed anywhere, and is good for nothing, to be thrown out of the body as a nuisance.
“Now let us follow these little organs, as they fly upward, to carry support to the hair, to make it grow. But, as they proceed upward, the ears will want serum—the eyes will want something for the eye-balls, and the organs about the eye will take that and work it up into the eyes, and cause them to grow; then proceed on to your joints, and along the bones, muscles and nerves; the joints want strength—it is a fluid called synovia, in physiology; then proceed to your finger nails.”
So you see the whole system is supported by the blood; all these vessels or supports go to every organ in the body, and are called secretions; if these secretions are obstructed by disease, they cannot perform their regular routine, or office, and the parts will gradually become infirm. The blood carries little atoms, or particles, to make all parts of the body grow, and which, you may perceive, are necessary to replace the atoms which are worn off by friction, in our motion, as there is a constant waste in every part of the body, or system.
Now let me return to the heart. It is not larger than a man’s fist, and is strong and muscular. It is, as I said before, situated slanting, or obliquely; both sides of the heart fill in the same instant, and then contract, shrink, and compresses, with as much force as a strong man could press it with his hand. Such is the admirable circulation of the blood, that this revolution goes regular, one hundred thousand times in twenty-four hours.
How can we but admire the creation of such a beautiful machine! Then consider how much resistance this poor heart has to overcome, in sending blood to all parts of the body, and the many obstructions in its way, which causes it to stop its motion, or it will quiver and throb, according as it is repulsed by those obstructions. How many there are who say, “My heart is diseased—the physician says so.” Now, my friends, not in one case of ten is the heart diseased; but it is obstructed in its revolutions, by not being able to send the blood through these little vessels, to all parts of the body; they are crooked, and the least impediment must necessarily cause agitation, or stop this great propeller.
There is a strong partition between the right and left sides of the heart, so that the right auricle and right ventricle, with their blood, brought back from the veins, can have nothing to do with the blood in the left auricle and left ventricle; it is, indeed, as if there were two hearts, placed side by side, and pressed closely together. We know not how the heart is kept in motion, nor can the wisest anatomist or physiologist in the world tell us; we know that the lungs have something to do in the case, and, when once set a-going, we can form some idea of what keeps it in motion—but, after all, the real causes of the continued movement of either the heart or lungs, has ever been a great mystery, and may possibly always remain so.