flisi'A.JfT lioiiizojf. 
• 1,13 
wore Concealed under that fresh foliage ; and the disposition 
of the plants, the grouping of so many inanimate objects, 
give the landscape all the charm of motion and of life. 
Seven months had now elapsed since we had been on the 
summit of the peak of Tenorifl’e, whence we surveyed p 
space of the globe equal to a fourth part of France. Tlu 
apparent horizon of the sea is there six leagues farther 
distant than at the top of the Silla, and yet we saw that 
horizon, at least for some time, very distinctly. It was 
strongly marked, and not confounded with tile adjacent 
strata of air. At the Silla, which is five hundred and fiftv 
toises lower than the peak of Tenerifle, the horizon, though 
nearer, continued invisible towards the north and north- 
north-east. Following with the eye the surface of the sea, 
which was smooth as glass, we were struck with the pro- 
gressive diminution of the reflected light. Where the visual 
ray touched the last limit of that surface, the water was lost 
among the superposed strata of air. This appearance has 
something in it very extraordinary. We expect to see the 
horizon level with the eye ; but, instead of distinguishing at 
this height a marked limit between the two elements, the 
more distant strata of water seem to be transformed into 
vapour, and mingled with the aerial ocean. I observed the 
same appearance, not in one spot of the horizon alone, but 
on an extent of more than a hundred and sixty degrees, 
along the Pacific, when I found myself for the first time on 
the pointed rock that commands the crater of Ficliincha ; a 
volcano, the elevation of which exceeds that of Mont Blanc. # 
The visibility of a very distant horizon depends, when there 
is no mirage, upon two distinct things: the quantity of 
light received on that part of the sea where the visual ray 
terminates ; and the extinction of the reflected light during 
its passage through the intermediate strata of air. It may 
happen, notwithstanding the serenity of the sky and the 
transparency of the atmosphere, that the ocean is -feebly 
illuminated at thirty or forty leagues’ distance ; or that the 
strata of air nearest the earth may extinguish a great deal 
of the light, by absorbing the rays that traverse them. 
The rouuded peak, or western dome of the Silla, con- 
* See Views of Nature, Bohn's edition, p. 358. 
2 V 
VOL. I. 
