268 THE WORK DONE. [BOOK i. 



equivalent to 3'21 meters of blood, this means that the left 

 ventricle is capable at its systole of lifting 180 grms. 3'21 m. high, 

 i.e. it does 578 gram-meters of work at each beat. Supposing the 

 heart to beat 72 times a minute, this would give for the day's 

 work of the left ventricle nearly 60,000 kilogram-meters. Calcu- 

 lating the work of the right ventricle at one-fourth that of the 

 left, the work of the whole heart during the day would amount to 

 75,000 kilogram-meters, which is just about the amount of work 

 done in the ascent of Snowdon by a tolerably heavy man. 



