"This balsam-fir," said Miss Harson as they stood near a tall, beautiful tree that tapered to a point, "has, you see, a straight, smooth trunk and tapers regularly and rapidly to the top. You will notice, too, that the leaves, which are needle-shaped and nearly flat, do not grow in clusters, but singly, and that their color is peculiar. There are faint white lines on the upper part and a silvery-blue tinge beneath, and this silvery look is produced by many lines of small, shining resinous dots. The deep-green bark, striped with gray, is full of balsam, or resin, known as balm of Gilead or Canada balsam, and highly valued as a cure for diseases of the lungs. The long cones are erect, or standing, and grow thickly near the ends of the upper branches. They have round, bluish-purple scales, and the soft color has a very pretty effect on the tree. They ripen every year, and the lively little squirrel, as he is called, feasts upon them, as the crossbill does on the cones of the stone-pine. But the mischievous little animal also barks the boughs and gnaws off the tops of the leading shoots, so that many trees are injured and defaced by his depredations."