Manchester Memoirs, Vol. Iv. (191 1), No. 7- n 



(2) Where similar homogeneous bodies are of the same 

 specific gravity, the larger tends to approach the centre 

 more rapidly. Cf. A (16 & 17), (8 & 14) ; C (12 & 13). 



(3) In bodies of the same shape and size but of 

 different specific gravities the lighter tends to approach 

 the centre more rapidly. Cf A (12 & 16), (18 & 19), 

 (7 & 21), (39 & 40), (46, 47 & 4S) ; C (9 & 10), (30 & 31 j, 

 (34 & 35)- 



(4) In non-homogeneous bodies of the same size, 

 shape and weight, the lower the centre of gravity the less 

 is the tendency to approach the centre. With the C.G. 

 sufficiently low down the body gradually works out from 

 the centre of the vortex. Cf A (19 & 20), (40 & 41), 

 (43, 44 & 45); C (10 & II), (31 & 32), (35 & 36;. Com- 

 paring A (21 & 22) it appears that the relative lightness 

 of cylinder 22 more than counterbalances the change in 



the relative position of the centre of gravity as compared 

 with cylinder 21. 



In homogeneous bodies of the same size and depth 

 of immersion, those more nearly approximating to a 

 circular form of cross section show the lesser tendency to 

 approach the centre, the difference becoming more 

 marked as the size increases. Cf A (i to 6, 27 to 32 & 33 

 to 38) ; (8 & 23), (12 & 25), (23 & 39) ; C (i to 5, 14 to 

 17 & 18 to 23) ; (24 & 30); (7 & 24). 



In vortices whose intensity is increased by increasing 

 the quantity of water discharged, either by increasing 

 the head or the size of the discharge orifice, the observed 

 phenomena are intensified. For bodies revolving in 

 <!quilibrium, the equilibrium circle is larger in the stronger 

 vortex, while the minimum size of body capable of re- 

 volving in equilibrium increases with the strength of 

 vortex. Cf tables A, B, and C. 



