JSTatural History of the Ocean^ ^c. 135 



Water Spouts, — At one period tbey were supposed to be 

 Volcanic* BerthoUet and Franklin thought them electric: 

 the clouds and water mutually attracting each other, and 

 they thought their idea was confirmed by the accompany- 

 ing lightning. Oliver supposed them occasioned by the 

 suction of a cloud. Perhaps the nearest approach to truth 

 is the supposition of the Hon. Capt. Napier. He supposes 

 that many opposite currents of wind, all pointing to a cer- 

 tain centre; and coming in contact with each other, with 

 unequal forces, cause a rotary motion or current of them- 

 selves round a central space, which, not partaking of an 

 equal, or its former pressure, naturally becomes rarified by 

 the existing heat, to such an extent, that it speedily acquires 

 a state in a great degree approximating to that of a vacuum. 



This continued rotary motion of the air forms a kind of 



whirlwind: and the pressure of the external atmosphere at 

 the base, forcing the water to a reasonable height up the 



rarified space within, it is then carried upwards by the me- 

 chanical action of the wind, in light and unconnected streaks. 

 The space at the bottom now becoming void, is regularly 

 replenished by the pressure from without, till the whole 

 spout is perfectly completed. 



The water having now arrived at the region of the clouds^ 

 it is naturally attracted, diffused and connected with and 

 among them; increasing in d^insity and extent, till the low- 

 er atmosphere becoming now lighter than the clouds above, 

 these enormous masses, gradually settling downwards, dis- 

 tend, burst, and are dissipated in rain. 



A notice of the inhabitants of the ocean belongs more 

 particularly to the zoologist. 1 shall give only two extracts 

 twidlng to show the immense number of minute animals la 

 the Greenland seas. They will at the same time exhibit 

 the close investigation and research of that accurate obser- 

 ver, Capt. Scoresby. 



On examining some olive green water, he found the num 

 ber of medusas to be immense. They were about one fourtli 

 of an inch asunder. In this proportion, a cubic inch of wa- 



ter must contain sixty-four: a cubic foot 110,592; a cubic 

 fathom 23,887,872; and a cubical mile 23,888,000,000,- 

 000,000. It may give a better conception of the amount of 

 medusae in this extent, if we calculate the length of time 

 that would be requisite, with ft certain number of persons, 



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