4 THE CANADIAN NATURALIST. 



ice. But here is another phenomenon, no less curious : if 

 you make a hole obliquely in a heap of snow, so that the 

 light shall not shine directly into it, you will see that the 

 light which is transmitted through the snow is of a brilliant 

 blue colour, varying in depth of tint, according to the thick- 

 ness of the mass. 



C. I perceive it is so. What is the cause of it ? 



F. The cause I cannot with certainty make known. 

 That blue is the natural colour of the purest water is proved 

 by two facts ; the first of which is however very little known 

 to landsmen ; namely, that the sea, when out of soundings, 

 is of a bright deep blue, (although a tumbler-full taken up 

 is as clear as pure spring- water,) the green tint of the sea 

 near shore, being caused by the nearness of the bottom. 

 The other fact is, that the blueness of the sky, distant 

 mountains, &c. depends on the particles of water held in 

 vapour in the atmosphere ; the tint of these objects being 

 deepened in intensity by an increase of moisture in the air. 

 I have thought that possibly the phenomenon we have just 

 noticed, may be but another exemplification of the same law; 

 the medium through which the light is transmitted being 

 but water frozen ; and that the continual breaking of the 

 rays of light through such a multitude of particles may have 

 the same effect as the loss of light in passing through a large 

 mass of water. But this is only a conjecture. 



C. There is a woodpecker in the act of boring that de- 

 cayed tree ; he makes the hollow woods echo with his loud 

 and rapid taps. By his grey back, scarlet poll, and spotted 

 wings, I know him to be the Hairy Woodpecker (Picus 

 Villosm). What can he find in that old tree ? 



F. The grubs of some insects. Many species of beetles, 



