THE ROYAL ARTILLERY INSTITUTION. 
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pour les projectiles oblongs, quand leur axe de figure coincide avec la direction du 
mouvement, nous avons admis, dans les limites des vitesses de 510 m:S a 360 m:S 
(1673 f.s. to 1181 f.s.) la resistance de l’air proportionelle au carre de la vitesse; 
dans les limites des vitesses de 360 m:s a 280 m:s (1181 f.s. to 919 f.s.) nous avons 
admise proportionelle a la sixieme puissance de la vitesse,” &c. 
In the theoretical treatment of the motion of a projectile, General Mayevski 
changes his law of resistance according to the velocity of the moving shot, while 
Mr. Bashforth uses the cubic law of resistance throughout, changing only the 
coefficient to suit the velocity. 
Professor Helie, from experiments made with elongated shot, moving with velo¬ 
cities 340 m:9 to 200 m:s (1115 f.s. to 656 f.s.), deduced a law of resistance which 
varied as the cube of the velocity, while the two more recent experimenters agree in 
giving the sixth power of the velocity as the best law when only one term is used* 
for this limit of velocity. 
