it as high up as he can reach, and again below, some three
feet down; and, while you are wondering at this seemingly wanton
destruction, he lifts the bar on high, throws his head back, and pours
down his thirsty throat a pint or more of pure cold water. This hidden
treasure is, strange as it may seem, the ascending sap, or rather the
ascending pure rain-water which has been taken up by the roots, and
is hurrying aloft, to be elaborated into sap, and leaf, and flower,
and fruit, and fresh tissue for the very stem up which it originally
climbed, and therefore it is that the woodman cuts the water-vine
through first at the top of the piece which he wants, and not at the
bottom; for so rapid is the ascent of the sap, that if he cut the stem
below, the water would have all fled upward before he could cut it off
above.

Meanwhile, the old story of Jack and the Bean-stalk comes into your
mind. In such a forest was the old dame's hut, and up such a bean-stalk
Jack climbed, to fight a giant and a castle high above. Why not? What
may not be up there? You look up into the green cloud, and long for
a moment to be a monkey. There may be monkeys up there over your
head,--burly red Howler, or tiny peevish Sapajou, peering down at you,
but you cannot peer up at them. The monkeys, and the parrots, and the
humming-birds, and the flowers, and all the beauty, are upstairs--up
above the green cloud. You are in "the empty nave of the cathedral," and
the service is being celebrated aloft in the blazing roof.

We will hope that, as you look up, you have not been careless enough to
walk on, for if you have you will be tripped up at once; nor to put your
hand out incautiously to rest it against a tree, or what not, for fear
of sharp thorns, ants, and wasp-nests. If you are all safe, your next
steps, probably, as you struggle through the bush between tree-trunks of
every possible size, will bring you face to face with huge upright walls
of seeming boards, whose rounded edges slope upward till, as your eye
follows them, you find them enter an enormous stem, perhaps round, like
one of the Norman pillars of Durham nave, and just as huge; perhaps
fluted, like one of William of Wykeham's columns at Winchester.

There is the stem, but where is the tree? Above the green cloud. You
struggle up to it between two of the board walls, but find it not so
easy to reach. Between you and it are half a dozen tough strings which
you had not noticed at first,--t