Take a sheet of stout note paper, Fig. 14, A, double it sharply down the centre, by the dotted line, then give it the two cuts at _a_ and _b_, and double those pieces sharply back, as at B; then, opening them again, cut the whole {132} into the form C; and then, pulling up the corners _c d_, stitch them together with a loose thread so that the points _c_ and _d_ shall be within half an inch of each other; and you will have a kind of triangular scoop, or shovel, with a stem, by which you can sufficiently hold it, D. 7. And from this easily constructed and tenable model, you may learn at once these following main facts about all leaves. {133} [I.] That they are not flat, but, however slightly, always hollowed into craters, or raised into hills, in one or another direction; so that any drawable outline of them does not in the least represent the real extent of their surfaces; and until you know how to draw a cup, or a mountain, rightly, you have no chance of drawing a leaf. My simple artist readers of long ago, when I told them to draw leaves, thought they could do them by the boughfull, whenever they liked. Alas, except by old William Hunt, and Burne Jones, I've not seen a leaf painted, since those burdocks of Turner's; far less sculptured--though one would think at first that was easier! Of which we shall have talk elsewhere; here I must go on to note fact number two, concerning leaves. {134} 8. [II.] The strength of their supporting stem consists not merely in the gathering together of all the fibres, but in gathering them essentially into the profile of the letter V, which you will see your doubled paper stem has; and of which you can feel the strength and use, in your hand, as you hold it. Gather a common plantain leaf, and look at the way it puts its round ribs together at the base, and you will understand the matter at once. The arrangement is modified and disguised in every possible way, according to the leaf's need: in the aspen, the leaf-stalk becomes an absolute vertical plank; and in the large trees is often almost rounded into the likeness of a fruit-stalk;--but, in all,[36] the essential structure is this doubled one; and in all, it opens at the place where the leaf joins the main stem, into a kind of cup, which holds next year's bud in the hollow of it.