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Show MECHANISM OF HUMAH HEART Average Rapidity of Cardiac Pulsation Pulsa-tion of Adult Male Is About 70 Beats Per Minute. In the human subject the average rapidity of the cardiac pulsation ot an adult male is about 70 beats per minute. These beats are more frequent fre-quent as a rule in young children and in women, and there are variations, within certain limits, in particular persons owing to peculiarities of or- -ganization. It would not necessarily be an abnormal sign to find in tome particular individuals the habitual frequency fre-quency of the heart's action from 61 to CO or from 70 individuals the habitual frequency of the heart's action is slower and more powerful in fully developed and muscular organizations or-ganizations and more rapid and feebler in those of slighter form. In animals the range is from 25 to 45 in the cold blooded and 50 upward in the warm blooded, except in the case of a horse, which has a very slow heart' beat, only 40 strokes a minute. The pulsations of men and all animals differ with the sea level also. The work of a healthy human heart has been shown to be equal to the feat of raising five tons four hundredweight hun-dredweight one foot per hour, or 125 tons in 24 hours. A curious calculation ha3 been made by Dr. Richardson, giving the work ot the heart in mileage. Presuming that the blood was thrown out of the heart at each pulsationMn the proportion ol 69 strokes per minute and at the assumed as-sumed force of nine feet, the mileage of the blood through the body might be taken as 207 yards per minute, seven miles per hour, 168 mile3 per day, 61.C20 miles per year, or 5,150,-SS6 5,150,-SS6 miles in a lifetime, 84 years. The number of beats of the heart in the same long life would reach the grand total of 2,SG9,776,000. . |