174 ACCOUNT OF THE ARCTIC REGIONS. 



brought down with the fresh water from the laniT. 

 But, in the main ocean, in deep water, the prevailing 

 colour is blue, or greenish blue. It may be observed, 

 that there is a good deal of deception in the colour of 

 the sea, owing to the effect of the sun, and the co- 

 lour of clouds ; and its true tinge can only be ob- 

 served, with accuracy, by looking downward through 

 a long tube, reacliing nearly to its surface, so as to 

 intercept the lateral rays of light, which, by their 

 reflection, produce the deception, and thus obtain a 

 clear view of the interior of the sea. The trunk 

 of the rudder answers this purpose tolerably well. 

 When thus examined, the colour of the sea is not 

 materially affected, either by sun or clouds. But, if 

 examined superficially, from an exposed situation, 

 the sea, in all places, will be found to vary in appear- 

 ance with every change in the state of the atmo- 

 sphere. Hence the surface generally partakes of the 

 colour of the clouds ; and, when the sky is chiefly 

 clear, a small cloud partially intercepting the sun's 

 rays, casts a deep brown or blackish shadow over the 

 surface, and sometimes gives the appearanceof shallow 

 water, or rocks, and thus occasions, in the navigator, 

 unnecessary alarm. It is not, therefore, the varying 

 aspect of the surface of the water that is meant by 

 the colour of the sea ; but the appearance of the in- 

 terior of a body of waters, when looked into through 

 a perpendicular tube. The only effect then pro- 

 duced by a change in the aspect of the sky, is to 



