A LIVING, SELF-ACTING PUMP. 295 
such a regimen it is not singular that so many thousands of 
children annually fall victims to stomach and intestinal diseases 
of various forms. In great numbers of cases early indiscretions ~ 
of this sort are the real causes of fully developed dyspepsia of 
later years.” 
A Livinc, SELF-ACTING PUMP AND THE ELIXIR OF LIFE. 
Poets and lovers wax eloquent about the heart, as though 
it were capable of thought. We love with our heart, so we are 
told. Well, the heart, in reality, is nothing more or less than a 
self-acting pump, composed of four chambers, and has not any 
sense at all. Love is the rousing into activity of certain brain 
centres. The heart is a power- 
ful muscle, or rather a combi- 
nation of muscles. The two top 
chambers are the auricles, the 
bottom ones are the ventricles. 
The purpose of the heart is to 
pump the blood through the 
body. The human heart, in 
size and shape, is almost identi- 
cal with that of a pig’s heart. 
The heart is situated just under 
the breast bone, in the chest 
cavity, which is known as the 
Fic. 121.—A section of the human stomach 
thorax. It is turned slightly to whichis the most abused and overworked 
i part of the mechanism of the body. 
the left side. (From Blackie’s Physiology.) 
The weight of the heart averages 8 to Io ounces in women, 
and 10 to 12 ounces in men. We really have two hearts joined 
together. The right side of the heart is for the purpose of 
pumping the blood up into the lungs. The left side is for driving 
it all over the body, hence the reason that the ventricle on the 
left side is three or four times as thick as that on the opposite 
side, because it has to pump the blood to the most distant parts 
of the body ; whereas its companion only has to drive the blood 
a very short distance. The Dugong, a warm-blooded animal 
which lives in the ocean, and which has given rise to the mermaid 
myth, has two hearts, quite separate. 
