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fefs this adhefive, generative, quality, when applied to the bark of trees.

IV. Another inftance of the compenfatory fyftem is in the autumnal crocus or meadow faffron, (cholcicum autumnale). I have pitied this poor plant a thousand times. Its bloffom rifes out of the ground in the most forlorn condition poffible; without a fheath, a fence, a calyx, or even a leaf to protect it: and that, not in the spring, not to be vifited by fummer funs, but under all the difadvantages of the declining year. When we come howeverto look more closely into the structure of this plant, we find that, instead of its being neglected, nature has gone out of her course to provide for its fecurity, and to make up to it for all its defects. The feed-veffel, which in other plants is fituated within the cup of the flower, or just beneath it, in this plant lies buried ten or twelve inches under ground within the bulbous root. The tube of the flower, which is feldom more than a few tenths of an inch long, in this plant extends down to 'the root. The ftyles always reach the feedveffel; but it is in this, by an elongation unknown to any other plant. All these fingu larities contribute to one end.

"As this plant bloffoms

bloffoms late in the year, and, probably, would not have time to ripen its feeds before the access of winter which would destroy them, Providence has contrived its ftructure fuch, that this important office may be performed at a depth in the earth out of reach of the ufual effects of froft*." That is to fay, in the autumn nothing is done above ground but the business of impregnation; which is an affair between the antheræ and the ftigmata. The maturation of the impregnated feed, which in other plants proceeds within a capfule, exposed together with the reft of the flower to the open air, is here carried on, and during the whole winter, within the heart, as we may fay, of the earth, that is, "out of the reach of the ufual effects of froft." But then a new difficulty prefents itfelf. Seeds, though perfected, are known not to vegetate at this depth in the earth. Our feeds therefore, though fo fafely lodged, would, after all, be loft to the purpose for which all feeds are intended. Left this fhould be the cafe, "a fecond admirable provifion is made to raise them above the furface when they are perfected, and to fow them

* Ib. p. 360.

at

at a proper distance:" viz. the germ grows up in the Spring, upon a fruit-ftalk, accompanied with leaves. The feeds now, in common with those of other plants, have the benefit of the fummer, and are fown upon the furface. The order of vegetation externally is this. The plant produces its flowers in September; its leaves and fruits in the spring following.

V. I give the account of the dionæa muscipula, an extraordinary American plant, as fome late authors have related it; but, whether we be yet enough acquainted with the plant to bring every part of this account to the teft of repeated and familiar obfervation, I am unable to fay. Its leaves are jointed, and furnished with two rows of ftrong prickles; their furfaces covered with a number of minute glands, which fecrete a fweet liquor, that allures the approach of flies. When these parts are touched by the legs of flies, the two lobes of the leaf instantly fpring up, the rows of prickles lock themselves faft together, and fqueeze the unwary animal to death." Here, under a new model, we recognise the ancient

* Smellie's Phil. of Nat. Hift. vol. i. p. 5.

plan

plan of nature; viz. the relation of parts and provisions to one another, to a common office, and to the utility of the organized body to which they belong. The attracting fyrup, the rows of ftrong prickles, their position fo as to interlock, the joints of the leaves; and, what is more than the reft, that fingular irritability of their surfaces, by which they close at a touch; all bear a contributory part in producing an effect, connected either with the defence, or with the nutrition of the plant.

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CHAPTER XXI.

THE ELEMENTS.

WHEN we come to the elements, we take

leave of our mechanics; because we come to thofe things, of the organization of which, if they be organized, we are confeffedly ignorant. This ignorance is implied by their name. To fay the truth, our investigations are stopped long before we arrive at this point. But then it is for our comfort to find, that a knowledge of the conftitution of the elements is not neceffary for us. For inftance, as Addifon has well obferved, "we know water fufficiently, when we know how to boil, how to freeze, how to evaporate, how to make it fresh, how to make it run or spout out, in what quantity and direction we please, without knowing what water is." The observation of this excellent writer has more propriety in it now, than it had at the time it was made: for the conftitution, and the conftituent parts, of water, appear in fome meafure to have been lately

discovered;

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