Ill 



The al)()\v fiinu'e is Cnse III, and shows the airouud a porabola in lou.t,'i- 

 tudinal section. This ease most nearly coincides with tlie aetnal condi- 

 tions, for lianl. of any f)f the three cases, and any variance discovered here 

 in tlie resnlts of the fonr nietliods are about wliat would occur in actual 

 practice, whik those discovered under Case II are limiting values. 



It being tlie object of the writer to discover the greatest variance that 

 could occur, thus obtaining limiting values, most of the computations were 

 under ("ase II. with a few test investigations under Case III, to obtain 

 values that would be encountered more often in practice. 



Method No. 1 depends njion the general form that the center of grav- 

 ity of individual prismoids is located a distance froui the mid-section to- 

 ward the larger section a distance 



I A 



.V 



— and Haul 



^ f. A - A' 

 For all i)ractical purposes it is exact. 



i Moments 

 ^Volumes. 



