CHEMICAL SCIENCE. 219 



posture, about 600 cubic inches per minute, at a rate of fourteen per 

 minute, and a depth of 43 cubic inches, and the rate of pulsation 

 was 75 per minute. Thus, during the exertion, the quantity of air 

 inspired was increased two-thirds, the depth of inspiration two and 

 a half times, and the rate of pulsation two and a half times. The 

 returns during the period of rest show that the effects of the labor 

 had not passed away in a quarter of an hour. Compared with the 

 results in the quiet sitting posture, the author stated that the effect 

 on the respiration was five and a half times, and on pulsation two 

 and a half times as great ; and taking together the three and three- 

 quarters hours of hard labor with a similar period of rest, he proved 

 that the effect upon the system of the eight hours' labor was equal 

 to that of twenty-four hours of those not condemned to hard labor ; 

 and that, if the whole twenty-four hours were taken together, the ef- 

 fect would probably be two-thirds greater than that of occupations 

 not laborious. He then contrasted those results with others which 

 he had obtained for the purposes of comparison. Thus, fast walking,, 

 at upwards of four miles per hour, caused a rate of respiration of 30 

 per minute, a depth of 80 cubic inches, and a total quantity per min- 

 ute of 2,400 cubic inches. The rate of pulsation was 130 per minute. 

 Ascending steps at the rate of speed of the treadwheel, viz., 640 

 yards per hour, caused the rate of respiration to be 22 per minute, 

 the depth 90 cubic inches, and total quantity per minute 1,986 cubic 

 inches, and a rate of pulsation of 114 per minute. Carrying 118 

 pounds at the rate of three miles per hour induced a rate of respira- 

 tion of 24^ times per minute, a depth of 90 cubic inches, and a total 

 quantity of 2,141 cubic inches per minute, with a rate of pulsation 

 of 189 per minute. Thus the labor of the treadwheel produces 

 greater effect upon the respiration than any of these modes of exer 

 tion, while the effect upon pulsation was greater in the last severe 

 labor only. The total quantity of air breathed per hour upon the 

 treadwheel, if the labor were continuous, would be 150,000 cubic 

 inches, as opposed to 2 7,000 inches in the quiet sitting posture ; and 

 the wear of the system would, upon the known principles of science, 

 be in a somewhat similar proportion. He then proceeds to consider 

 the effect of this exertion upon the system, and shows that the 

 excessive exercise of the lungs and heart must ultimately lead to 

 phthisic, asthma, emphysema, congestion of various or-gans, and dis- 

 ease of the heart ; and in persons with diminished vital capacity 

 of the lungs, and weak hearts, the effect must sooner be very seri- 

 ous. In reference to food, the author is of opinion that the repara- 

 tive (nitrogenous) food, as flesh and bread, is ample, and requires 

 revision only in the better distribution of it; as, for example, the 

 removal of two or three ounces of the six ounces of cooked meat 

 allowed at the dinner four times per week, to the breakfast, which 

 consists only of bread a ad cocoa. He also points out the importance, 

 and especially to those who masticate imperfectly, of rendering the 

 meat tender, and of allowing more time between the meal and the 

 return to the hard labor. The great and most serious defect is in 

 the respiratory food, since neither fat not sugar is allowed except in 

 combination, as in the ox-heads, or in the briskets of beef, and in 

 the milk and cocoa. No sugar, lard, suet, bacon, or butter is al- 



