Micrographia, by Robert Hooke

Observ. xxiv. Of the surfaces of Rosemary, and other leaves.

This which is delineated within the circle of the second Figure of the 14. Scheme, is a small part of Schem. 14.
Fig. 2.
the back or under side of a leaf of Rosemary, which I did not therefore make choice of because it had any thing peculiar which was not observable with a Microscope in several other Plants, but because it exhibits at one view,

First, a smooth and shining surface, namely, AB, which is a part of the upper side of the leaf, that by a kind of hem or doubling of the leaf appears on this side. There are multitudes of leaves, which surfaces are like this smooth, and as it were quilted, which look like a curious quilted bagg of green Silk, or like a Bladder, or some such pliable transparent substance, full stuffed out with a green juice or liquor; the surface of Rue, or Herbgrass, is polish'd, and all over indented, or pitted, like the Silk-worm's Egg, which I shall anon describe; the smooth surfaces of other Plants are otherwise quilted, Nature in this, as it were, expressing her Needle-work, or imbroidery.

Next a downy or bushy surface, such as is all the under side almost, appearing through the Microscope much like a thicket of bushes, and with this kind of Down or Hair the leaves and stalks of multitudes of Vegetables are covered; and there seems to be as great a variety in the shape, bulk, and manner of the growing of these secundary Plants, as I may call them (they being, as it were, a Plant growing out of a Plant, or somewhat like the hairs of Animals) as there is to be found amongst small shrubs that compose bushes; but for the most part, they consist of small transparent parts, some of which grow in the shape of small Needles or Bodkins, as on the Thistle, Cowag-ecod and Nettle; others in the form of Cat's claws, as in Cliders, the beards of Barley, the edges of several sorts of Grass and Reeds, &c. in other, as Coltsfoot, Rose-campion, Aps, Poplar, Willow, and almost all other downy Plants, they grow in the form of bushes very much diversify'd in each particular Plant, That which I have before in the 19. Observation noted on Rose-leaves, is of a quite differing kind, and seems indeed a real Vegetable, distinct from the leaf.

Thirdly, among these small bushes are observable an infinite company of small round Balls, exactly Globular, and very much resembling Pearls, namely, CCCC, of these there maybe multitudes observ'd in Sage, and several other Plants, which I suppose was the reason why Athanasius Kircher supposed them to be all cover'd with Spiders Eggs, or young Spiders, which indeed is nothing else but some kind of gummous exsudation, which is always much of the same bigness. At first sight of these, I confess, I imagin'd that they might have been some kind of matrices, or nourishing receptacles for some small Insect, just as I have found Oak-apples, and multitudes of such other large excrescencies on the leaves and other parts of Trees and shrubs to be for Flyes, and divers other Insects, but observing them to be there all the year, and scarce at all to change their magnitude, that conjecture seem'd not so probable. But what ever be the use of it, it affords a very pleasant object through the Microscope, and may, perhaps, upon further examination, prove very luciferous.

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Last updated Monday, March 17, 2014 at 16:42