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cottony underneath, but when full grown are smooth; they are slightly heart-shaped, smaller and 
more approaching to circular than in the preceding, with a few angular teeth on the edges/* Lin- 
neeus says, that they are rolled inwards at the edge, and that they have two glands running one into 
the other on the inner side above the base. He also observes from Gouan, that the leaf-stalks are 
flatted towards the end, whence the perpetual trembling of the leaves with every breath of wind. 
But the petioles being flat in the White and Black Poplars as well as in this, Dr. Stokes accounts 
better for the phenomenon, from the plane of the long leaf-stalks being at right angles to that of the 
leaves, which allows them a much freer motion than could have taken place had their planes been 
parallel. This trembling of the leaves has been so generally noticed as to have become proverbial 
among us; and Mr. Lightfoot informs us that the Highlanders of Scotland account for it, from a 
superstitious notion that our Saviour’s cross was made of this tree, and that therefore the leaves can 
never rest. 
Of the Aspen, says Evelyn, our woodmen make hoops, fire-wood, coals, &c. and the bark of 
young trees, in some countries, serves for candle or torch-wood. Pie thrusts down a more searching 
foot, and takes it ill to have his head cut off, as the same author quaintly expresses it. Villars also 
says that it will not bear lopping, like the Black Poplar. 
This tree is of speedy growth, and will grow in any situation or soil, but worst in clay. It im¬ 
poverishes the land: its leaves destroy the grass, and the numerous shoots of the roots spread so near 
the surface, that they will not permit any thing else to grow. The wood is extremely light, white, 
smooth, woolly, soft, durable in the air. The bark is the favourite food of beavers .p Pannels or 
pack-saddles, canns, milk-pails, clogs, pattens, &c. are made of the wood.J 
The leaves and leaf-stalks sometimes are set with red glandular substances, about the size of a 
pea, which are the nests of Tipula juniperina. 
• Native of Europe, from Sweden to Italy; in moist woods and in boggy ground. 
Species 3 . Black Poplar Tree . (Populus Nigra.) 
The Black Poplar has a naked lofty trunk, covered with an ash-coloured bark, and a regular 
handsome head.§ Leaves slightly notched on their edges, smooth on both sides, and of a light green 
colour. They have no glands at the base, but the serratures are glandular on the inner side. || The 
petioles are yellowish.^ According to Linnseus, the stamens are as many again as in P. tremula: 
Leers says they are sixteen in number. Mr. Miller observes that the catkins of this sort are shorter 
than those of the two former. Capsule compressed a little at the top and somewhat acuminate, the 
rest turgidly lenticular, one-celled; valves concave spreading horizontally. Seeds oblong roundish, 
whitish; waving with hairs at top four times as long as the seed. 
This is a tree of quick growth, and on the banks of rivers, and in moist situations it grows up to 
a great height, throwing out numberless suckers from the roots. It loves a moist black soil, and bears 
cropping well. The bark, being light cork, serves to support the nets of fishermen. The wood is 
not apt to splinter: it is light and soft, and sometimes used by turners. It is incomparable, says 
Mr. Evelyn, for all sorts of white wooden vessels, as trays, bowls, and other turner’s ware; and is of 
especial use for the bellows-maker, because it is almost of the nature of cork, and for ship-pumps, 
though not very solid, yet very close and yet light; so as it may be used for the soles, as well as 
* Lightfoot. 
§ Idem. 
t Withering. 
(I Linn. 
J Lightfoot. 
% Withering. 
