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THE POPULAR SCIENCE MONTHLY. 



Walking in the sea 



" on land at 1 mile per hour 

 Riding on horseback at the walking pace . 

 Walking at 2 miles per hour . 

 Riding on horseback at the cantering pace 

 Walking at 3 miles per hour . 

 Riding moderately 



Descending steps at 640 yards perpendicular per hour 

 Walking at 3 miles per hour and carrying 34 lbs. 



" " " " 62 lbs. . 



Riding on horseback at the trotting pace . 



Swimming at good speed 



Ascending steps at 640 yards perpendicular per hour 

 Walking at 3 miles per hour and carrying 118 lbs. 



" 4 miles per hour 



The tread-wheel, ascending 45 steps per minute 

 Running at 6 miles per hour 



Another table, from the same series of experiments, 

 same effect on the basis of the amount of carbonic acid evolved by 

 respiration per minute : 



No. i. 



In profound sleep, lying posture 4.5 grains. 



In light sleep, " 4.99 " 



Scarcely awake, 1} a. m. 5.7 " 



". " 1\ " 5.94 " 



" " 6 " 6.1 " 



Walking at 2 miles per hour 18.1 " 



" 3 " " 25.83 " 



Tread-wheel, ascending 28.15 feet per minute . . . 43.36 " 



Thus it is possible that the amount of vital change proceeding in 

 the body may be ten times greater in one state than in another, and it 

 follows that a proportionate quantity of food will be required to sus- 

 tain it. 







LTJNAK TEMPEEATUKES. 



POETS have so long sung of the cold, chaste Moon, pallid with 

 weariness of her long watch upon the Earth (according to the 

 image used alike by Wordsworth and Shelley), that it seems strange to 

 learn from science that the full moon is so intensely hot that no creat- 

 ure known to us could long endure contact with her heated surface. 

 Such is the latest news which science has brought us respecting our 

 satellite. The news is not altogether unexpected ; in fact, reasoning 

 had shown, long before the fact had been demonstrated, that it must 

 be so. The astronomer knows that the surface of the moon is exposed 

 during the long lunar day, lasting a fortnight of our terrestrial time, 

 to the rays of a sun as powerful as that which gives us our daily heat. 



