Prof. Loomis on Bodies falling through the Atmosphere. 69 
In making these computations I was obliged to assume a prob- 
able value of ¢ for the purpose of computing v and ¢; but the 
w, 
value of ¢ deduced from the formula c= pra 3S but slightly af- 
fected by an error in the first assumed value of ¢. In order how- 
ever to eliminate even this small influence, having computed the 
value of ¢ by these formule, I repeated the computation for v and 
t with the value of ¢ thus deduced, by which means I obtained a 
second determination of c which is almost wholly independent 
of the first assumed value. 








| Weights of |Diamet’rs of Whole times| Velocity in |Time of fall-| Coefficient |Do. reduced toa 
the bladders,|the bladders| of falling. | falling 10 ft.| ing 10 feet. | of resistance. | sphere of 5 in. 
grains, | inches. ary 8. 
128 528 19 14-200 0°9955 0013816 *0012390 
156 5:19 17 15581 0°9528 0013376 "0012415 
1375 53 185 14539 | 09844 | ‘0014047 | -0012501 
97 5°26 22 12°375 10690 0014223 “0012852 
| 99125 | 5 21-125'| 12°91! 10450 70013508 0013308 





_ The mean of the preceding values of ¢ for a sphere of 5 inches 
in diameter is 0012693, whence for a velocity of 15 feet, which 
is about the terminal velocity in the preceding experiments, the 
resistance on a sphere 5 inches in diameter is 2856 ounces. 
In the year 1802, a great number of experiments on falling 
bodies were made by Benzenberg in the tower of St. Michael’s 
church at Hamburg. Metallic balls about one and a half inches 
in diameter were allowed to fall from heights varying from 25 to 
340 French feet, and the times of descent were measured by a 
watch having a hand which made one revolution per second. 
‘Y ese experiments were performed with the greatest care; but 
since the specific gravity of the balls employed was more than 
ten times that of water, they do not appear to me as well adapted 
to indicate the amount of resistance, especially for smal! veloci- 
tes, as the experiments of Newton. 
ewton’s experiments have furnished us the resistance on a 
sphere 5 inches in diameter, at the two velocities of 15 and 30 
feet per second. We will now compare these results with those 
obtained by Hutton with the whirling machine. Hutton deter- 
mined the resistance upon a sphere of pasteboard 6 inches in 
diameter, for velocities from 3 to 20 feet per second. I have re- 
duced these results to a sphere 5 inches in diameter by assuming 
