176 OUTLINES OF NATURAL PHILOSOPHY, 



SECT. II. 



SOLID BODIES FLOATING ON FLUIDS, 



259. A SOLID floating on a fluid specifically 

 heavier than itself, will be in equilibria when it has 

 sunk so far, that the weight of the fluid displaced 

 is equal to the weight of the whole solid, and 

 when the centres of gravity of the whole solid, 

 and of the part immersed, are in the same vertical 

 line. 



ARCHIMEDES, de Humido fnsidentibus, Kb. i. BOSSUT 

 Hydrodyn. torn. i. chap. 12. 



Hence every solid of revolution, and in general eVery 

 solid having an axis to which the opposite sides are 

 similarly related, if it be specifically lighter than 

 a fluid, and if it be placed in the fluid with its axis 

 vertical, may sink to a position in which it will 

 remain in equilibria. 



There are always two opposite positions of equili- 

 brium in such bodies ; but there is only one of 

 them in which the body can float permanently. 



260. A prism, of which the triangle ABC 

 (fig. 22L), is a transverse section, being supposed 



homogeneous, 



