COLOURS OF THE SEA. 25 



different circumstances, that altogether occasion a change which can- 

 not be produced without that general concurrence, which does not of 

 course exist to operate- upon the plumage of a cage bird ; nor at all 

 times upon a bird even in a state of liberty : and we can thus easily 

 account for the curious and often-noticed fact, of many wild linnets 

 passing the summer without ever acquiring the scarlet colour upon 

 the breast. A circumstance which has caused a great deal of specu- 

 lation and embarrassment among naturalists. It may be remarked, in 

 conclusion, that many birds actually change their plumage twice in the 

 year, of which the male Whidah bird of Africa is a familiar example- 



Tooting, Surrey, Dec. 6th, 1832. 



ON THE COLOUR OF THE SEA. 



BY COLONEL BORY DE ST. VINCENT.* 



THOSE who have been accustomed to a life confined in the interior of 

 countries, where only rivulets and shallow rivers flow, where clear 

 fountains rise, or muddy currents roll along, view with admiration the 

 first appearance of the sea, as from the shore they regard the pure and 

 sparkling green complexion of its waters, a colour which indeed seems 

 peculiar to itself. The wonder is increased, when a portion of its water, 

 passed into a vessel, is observed to retain no trace of that very peculiar 

 colour, and to be perfectly clear. Its transparency is such, that in 

 places undefined by filth or dirt, the sand may be distinguished at the 

 bottom of its bed at a considerable depth, and stones and shells of the 

 smallest size, which lie there, appear then bright and resplendenf. 

 Marine plants, especially the corallines, beam in it with the greatest 

 splendour ; and all productions of this nature elegantly shaded, whilst 

 they are sunk beneath the surface of the water ; but as soon as they 

 are taken out, this beauty vanishes. Certain Cystoceira, called by us 

 Iridea, as well as many Alcyonia, which, in their fostering element 

 shine in the colours of the rainbow, or in the finest tints of purple 

 and orange, seem there tinged with black, yellow, or simply of a brown 

 or dark violet hue, when cast upon the bank of the shore, lose their 

 attractions by exposure to the atmospheric air. As the light pene- 

 trates the abyss of waters, and during a cloudless day, as we enjoy an 

 excursion on its surface, the waves appear coloured in such a manner 



* Translated from the French, by the Editor. 



