An Ocean of Azure 



overcome the real ocean-colour. One hardly 

 understands how intense such a sky-reflection 

 may be, until one has watched the whole sea 

 transformed into glowing crimson or gold from 

 a radiant sunset. 



Much the same perplexity has been felt about 

 the blue colour of air, as about the blue colour 

 of the ocean ; and much the same course of 

 explanation has been followed. Its blueness 

 was long maintained to be due only or mainly 

 to the " scattering of sunlight " by infinite 

 numbers of floating dust-specks, which also 

 serve to account for the golden and crimson 

 tints of sunset. It now appears that oxygen, 

 an important element in the atmosphere, has a 

 faint blue tint of its own, like water, which 

 at least helps to answer for the blue of the 

 air. 



We may therefore say of Water that it is 

 believed to be transparently and intrinsically 

 blue ; and that its colour, though not actually 

 due to floating specks of dust and other im- 

 purities, is a good deal affected by them. Such 

 materials in the Ocean help to modify its colour- 

 ing, sometimes deepening it, sometimes adding 

 to its brilliance, sometimes deadening its bright- 

 ness, sometimes turning it green or yellow. Care- 



77 



