HYDROGHAPHlbAL SURVEY. 179 



thrAt in that of an olive-green colour ; and also oc- 

 curring, but in lesser quantity, in the bluish-green 

 water. The number of medusae in the olive-green 

 sea was found to be immense. They were about 

 one- fourth of an inch asunder. In this propor- 

 tion, a cubic inch of water must contain 64 ; a 

 cubic foot 110,592; a cubic fathom 23,887,872; 

 and a cubical mile about 23,888,000,000,000,000 ! 

 From soundings made in the situation where 

 these animals were found, it is probable the sea 

 is upwards of a mile in depth ; but whether 

 these substances occupy the whole depth is un- 

 certain. Provided, however, the depth to which 

 they extend be but 250 fathoms, the above im- 

 mense number of one species may occur in a space 

 of two miles square. It may give a better concep- 

 tion of the amount of medusae in this extent, if 

 we calculate the length of time that would be 

 requisite, with a certain number of persons, for 

 counting this number. Allowing that one person 

 could count a million in seven days, which is barely 

 possible, it would have required, that 80,000 per- 

 sons should have started at the creation of the world, 

 to complete the enumeration at the present time ! 



What a stupendous idea this fact gives of the 

 immensity of creation, and of the bounty of Divine 

 Providence, in furnishing such a profusion of life in 

 a region so remote from tlie habitations of men ! 

 But if the number of animals in a space of two 



m2 



