ZODIACAL LIGHT. 
4,91 
trees tw enty-two feet and a half in diameter near the roots. 
These ligneous ridges sometimes separate from the trunk at 
a height of eight feet, and are transformed into cylindrical 
roots two feet thick. The tree looks as if it were supported 
by buttresses. This scaffolding however does not penetrate 
very deep into the earth. The lateral roots wind at the 
surface of the ground, and if at twenty feet distance from 
the trunk they are cut with a hatchet, wo see gushing out 
the milkv juice of the fig-tree, which, when deprived of the 
vital influence of the organs of the tree, is altered and 
coagulates. What a wonderful combination of cells and 
vessels exist in these vegetable masses, in these gigantic 
trees of the torrid zone, which without interruption, perhaps 
during the space of a thousand years, prepare nutritious 
fluids, raise them to the height of one hundred and eighty 
feet, convey them down again to the ground, and conceal, 
beneath a rough and hard bark, under inanimate layers of 
ligneous matter, all the movements of organic life ! 
I availed myself of the clearness of the nights, to observe 
at the plantation of Tuy two emersions of the first and third 
satellites of Jupiter. These two observations gave, accord- 
ing to the tables of Delambre, long. 4 h 39' 14" ; and by the 
chronometer I found 4 h 39' 10". During my stay in the 
valleys of the Tuy and Aragua the zodiacal light appeared 
almost every night with extraordinary brilliancy. I had 
perceived it for the first time between the tropics at Caracas, 
on the 18th of January, after seven in the evening. The 
point of the pyramid was at the height of 53°. The light 
totally disappeared at 9 h 35' (apparent time), nearly 3 h 50' 
after sunset, without any diminution in the serenity of the 
sky. La Caille, in his voyage to Bio Janeiro and the Cape, 
was struck with the beautiful appearance displayed by the 
zodiacal light within the tropics, not so much on account 
of its less inclined position, as of the greater transparency 
of the air.* It may appear singular, that Childrey and 
Dominic Cassini, navigators who were well acquainted with 
the seas of the two Indies, did not at a much earlier period 
direct the attention of scientific Europo to this light, and 
its regular form and progress. Until the middle of the 
* The great serenity of the air caused this phenomenon to be remarked, 
(i 1GG8, in the arid plains of Persia. 
