SOME OBSERVATIONS ON NIAGARA. 219 



the bend of the precipice to the northeast, the outlet comes into 

 view. 



The Niagara season had ended ; the chatter of sight-seers had 

 ceased, and the scene presented itself as one of holy seclusion and 

 beauty. I went down to the river's edge, where the weird loneliness 

 and loveliness seemed to increase. The basin is enclosed by high and 

 almost precipitous banks covered, when I was there, with russet 

 woods. A kind of mystery attaches itself to gyrating water, due per- 

 haps to the fact that we ai*e to some extent ignorant of the direction 

 of its force. It is said that at certain points of the whirlpool pine- 

 trees are sucked down, to be ejected mysteriously elsewhere. The 

 water is of the brightest emerald-green. The gorge through which it 

 escapes is narrow, and the motion of the river swift though silent. 

 The surface is steeply inclined, but it is perfectly unbroken. There are 

 no lateral waves, no ripples with their breaking bubbles to raise a 

 murmur; while the depth is here too great to allow the inequality of 

 the bed to ruffle the surface. Nothing can be more beautiful than this 

 sloping, liquid mirror formed by the Niagara in sliding from the 

 whirlpool. 



The green color is, I think, correctly accounted for in the " Hours 

 of Exercise in the Alps." In crossing the Atlantic I had frequent op- 

 portunities of testing the explanation there given. Looked properly 

 down upon, there are portions of the ocean to which we should hardly 

 ascribe a trace of blue ; at the most a hint of indigo reaches the eye. 

 The water, indeed, is practically blach, and this is an indication both 

 of its depth and its freedom from mechanically-suspended matter. In 

 small thicknesses water is sensibly transparent to all kinds of light ; 

 but, as the thickness increases, the rays of low refrangibility are first 

 absorbed, and after them the other rays. Where, therefore, the water 

 is very deep and very pure, all the colors are absorbed, and such water 

 ought to appear black, as no light is sent from its interior to the eye. 

 The approximation of the Atlantic Ocean to this condition is an indi- 

 cation of its extreme purity. 



Throw a white pebble into such water; as it sinks it becomes 

 greener and greener, and, before it disappears, it reaches a vivid blue- 

 green. Break such a pebble into fragments, each of these will behave 

 like the unbroken mass ; grind the pebble to powder, every particle 

 will yield its modicum of green ; and, if the particles be so fine as to 

 remain suspended in the water, the scattered light will be a uniform 

 green. Hence the greenness of shoal water. You go to bed with the 

 black Atlantic around you. You rise in the morning and find it a 

 vivid green ; and you correctly infer that you are crossing the bank 

 of Newfoundland. Such water is found charged with fine matter in a 

 state of mechanical suspension. The light from the bottom may some- 

 times come into play, but it is not necessary. A storm can render the 



