58 
OF LEAVES. 
Leaves with resjyect to Magnitude, 
Leaves vary in size, from the small leaves of some of the forest- 
trees of our climate, to the spreading Palms and Bananas of the tor- 
rid zone. As we approach the torrid zone, the leaves increase in 
magnitude ; we can, however, scarcely credit the reports of travel- 
lers, who say, that the Talipot-tree, in the Island of Ceylon, produces 
leaves of such size, that twenty persons may be sheltered by one sin- 
gle leaf Although this account may be exaggerated, there is no 
doubt of the fact, that the leaves of the torrid zone are of a wonder- 
ful size ; and that whole famihes, in 'those regions, can make their 
habitations under the branches of trees. Here we see the care of a 
kind Providence, which, in countries parched the greater part of the 
year by a vertical sun, has formed such refreshing shelters. Mungo 
Park, in his travels in Africa, remarks upon the many important uses 
of palm-leaves ; serving as covering to cottages, baskets for holding 
fruit, and umbrellas for defence against rain or sun. These leaves 
answer as a substitute for paper, and were so used by the eastern 
nations. Many suppose that the scriptures of the Old Testament 
were originally committed to palm-leaves. 
The magnitude of leaves often bears no proportion to the size of 
the plants to which they belong. The oak, and other forest-trees, 
bear leaves, which appear very diminutive, when compared with 
those of the cabbage, or burdock. 
Leaves, with respect to Duration^ are, 
Caducous^ such as fall before the end of summer ; 
Deciduous, falhng at the commencement of winter ; this is the case 
with the leaves of most plants, as far as 30'' or 40'' from the equator ; 
Pei-sistent, or permanent, remaining on the stem and branches, 
amidst the changes of temperature ; as the leaves of the pine and 
box; 
Evergreen, preserving their greenness through the year ; as the fir- 
tree and pine, and generally all cone-bearing and resinous trees ; 
these change their leaves annually, but the young leaves appearing 
before the old ones decay, the plant is always green. 
In our climate, the leaves are mostly deciduous, returning in au- 
tumn to their original dust, and enriching the soil from which they 
had derived their nourishment. In the regions of the torrid zone, 
the leaves are mostly persistent and evergreen ; they seldom fade or 
decay in less than six years ; but the same trees, removed to our 
climate, sometimes become annual plants, losing their foliage every 
year. The passion-flower is an evergreen in a more southern cli- 
mate. 
Leaves with respect to Colour. 
Leaves have not that brilliancy of colour which is seen in the co- 
rolla or blossom; but the beauty of the corolla, like most other exter- 
nal beauty, has only a transient existence; while the less showy leaf 
remains fresh and verdant after the flower has withered away. 
The substance of leaves is so constituted as to absorb all the rays 
of light except green ^ this colour is of all others best adapted to the 
extreme sensibility of our organs of sight. Thus, in evident accom- 
modation to our sense of vision, the ordinary dress of nature is of 
the only colour upon which our eyes, for any length of time, can 
rest without pain. 
But although green is almost the only colour which leaves reflect, 
the variety of its shades is almost innumerable. 
Palm-leaves— Leaves not corresponding in magnitude to the size of the plant—Du- 
ration—Colour of leaves— Different shades in the colour of leaves. 
