69 
Prof. J. Milne — On the Flotation of Icebergs. 
WATER LEVE 
"Wehavehere the solution to two theoretical cases of supposed bodies 
of ice floating in sea- 
water, which I think , 
will considerably aid us 
in forming some idea as 
to the depth to whicli 
icebergs extend beneatb 
the surface of the water, 
— the practical solution 
of which problem is sur- 
rounded with so much 
difficulty. The results 
are obtained from two 
regulär solids, but yet it 
is evident that they can 
be roughly applied to an y 
solids which approxim- 
ateto suchforms. Now 
from CaseI.,wherecones 
floating apex do wn wards 
are considered, it is 
evidently possible for 
floating ice to have a 
depth below the surface 
of the water in com- 
parison to that which is Fig. 1. 
above immensely greater than has generally been believed. But 
the question now is, have forms approximating to such inverted 
cones any existence in nature ? All that I can say to the contrary 
is by appealing to the results of observation and to the consequences 
of degradation upon a block of ice after leaving its parent the 
glacier, — both of which, as pointed out before (Geol. Mag. 1876, 
p. 306), appear unfavourable to such views. 
c 
I might also add, as another argument against the probability of 
ice extending to abyssal depths, that pressure tends to liquefy ice, 
or, in other words, to lower the freezing-point of water, and ice 
at great depths is under great pressure. For example, ice at the 
