42 



TIDES. 



forests, and its verdant pasture-lands. And as 

 the sandy tracts or shingly beds are bare and 

 devoid of vegetative life on the upper earth, so 

 are they also in the sea below; while submarine 

 forests lift their branches towards the light of the 

 sun, and submarine herbage waves its many- 

 coloured leaves in the rolling sea, just as flowers 

 and leaves bend to the breezes above. For in 

 the kingdom of Ocean, water is the atmosphere, 

 and, like its more ethereal relative, is ever rolling, 

 and ever changing. 



Let us now visit the boundary line of the two 

 great kingdoms, Earth and Water, and though 

 belonging to the former, extend our researches as 

 far as possible into the latter. 



Throughout the preceding pages it will be 

 noticed that the expression "at low water" is 

 constantly used. 'Now, this expression is quite 

 necessary ; for were the sea always to remain at 

 the same height, our knowledge of its wonders 

 would be wofully circumscribed. It is little 

 enough even now, but that little would be almost 

 reduced to nothing were there no alternations oi 

 high and low water. 



Of the theory of tides there is here no oppor- 

 tunity to speak, for it is a most complex subject, 

 and even to give a hasty sketch would occupy 



