9 z THE WALKS ABROAD OF 



" But probably they obtain their compensation by 

 making some fresh excursions at greater depths. 

 There must be scattered over the ocean some im- 

 mensely deep places ; and when a fish is tired of the 

 surface, I imagine there is nothing to prevent his 



SUBMARINE EXPLORATIONS OF THE ' ' TALISMAN. ' ' SPONGE (Roltento). 



going lower down and ruralising at a depth of say 

 eight or ten thousand feet." 



*' No, no ! This very year some curious observations 

 have been made on this subject. Without being a 

 great physicist, you may be aware that the pressure 

 increases in proportion to the depth. Well, it was 

 desired to find out how fish behave at pressures of 



