of Fluids, compared with the best Experiments. 255 



in which the time of describing seventy-two feet was observed. 

 Five trials were made with each change of form, except with 

 the most acute prows, which were tried only thrice, and in the 

 latter the results were not so regular as the others. The fol- 

 lowing table contains the mean resistances as Bossut has col- 

 lected them, the resistance of the parallelepiped being denoted 

 by 10000. 



The equation applying to this case is t^tv 2 sin 3 a -f- 1 + 



128-76 



0*0066 



f — l 8 i^ J ; and neglecting the difference be- 

 tween the measures, the resistance must be 10000 when sin 

 a = l, consequently 0*3285 f 2 sin 3 a -fl-f '0445 (s-h ^-)^ 

 is the expression for other angles. 



The numbers in the fourth column ought to represent the 

 resistances ; and as the difference between these and Bossut's 

 mean results are not greater than the differences among the 

 trials with the same form, in any case we may, I think, con- 



* See Bossut's Hydrodynamique. torn. ii. p. 411, or Robison's Mechani- 

 cal Philosophy, vol. ii. p. 295. Vince's Hydrostatics, sect. iii. Dr. Hut- 

 ton's Course of Mathematics for the Military Academy, vol. ii. Problem xix. 

 p. 353. 



elude 



