ITS VAEIETT OF COLOUR 29 



CHAPTER lY. 



VARIOUS COLOURS OF SEA WATER. — REFLECTIONS, TRANSPARENCY, AND PROPER 

 COLOUR. — TEMPERATURE OF THE DEPTHS OP THE SEA. 



Owing to the double property which w^ater possesses of reflecting 

 light and allowing its rays to penetrate to a great depth, it presents 

 successively the most varied colours, the most delicate tints, with 

 alternations the most fugitive and changeable that are to be found in 

 nature. The sea produces and at the same time modifies the varied 

 face of the heavens with all the play and gradation of light and shade. 

 At dawn, the surface of the water is gently brightened by the glim- 

 mering of the atmosphere as yet pale and faint ; then the sparkling 

 of the waves becomes more brilliant, and the full light of day pours 

 a flood of fire upon the billows. The least movement in the air is be- 

 trayed by a change in the aspect of the water, every cloud in passing 

 mirrors itself with the forms and shades of its vapours, every breath 

 of wind that just curls the waves renews the harmony of the change- 

 able colouring on the face of the ocean. And when evening comes, 

 the sea reflects back to the sky all its splendour of purple and flame. 

 It is then that we see on the horizon, " two suns appear one in front 

 of the other." 



But the water does not owe its beauty to the splendour of the sky 

 alone, it is beautiful also from its transparency ; whilst the substances 

 suspended in the liquid mass, which are visible to a considerable depth, 

 modify by their own colour the general tint of the sea. The animals, 

 fish or cetaceans, which come to the surface or glide swiftly through 

 the waves, cause them suddenly to glitter with changing reflections 

 of grey, rose, green, and silver. The fuci, too, growing beneath the 

 water, vary the aspect of the liquid strata which cover them, and where 

 these beds of plants alternate with ridges of bare rock, or tracts of 

 sand, the sea presents a wonderful mixture of different shades with 

 blended and tremulous outlines. In those latitudes where the 

 water is very transparent, the colour of the ground may be thus dis- 

 tinctly seen at 10, 20, or even 25 fathoms below the surface, 

 which navigators have confirmed by scientific observations made 



