trivance. It does not disprove the contrivance; it only removes it a little farther back. Who, to use our author's own language, "adapted the objects?" Who gave such a quality to these connate parts, as to be susceptible of different stimulation;" as to be "excited" each only by its own element, and precisely by that which the success of the vegetation requires? I say, "which the success of the vegetation requires:" for the toil of the husbandman would have been in vain; his laborious and expensive preparation of the ground in vain; if the event must, after all, depend upon the position in which the scattered seed was sown Not one seed out of a hundred would fall in a right di rection.

Our second observation is upon a general property of climbing plants, which is strictly mechanical. In these plants, from each knot or joint, or as botanists call it, axilla, of the plant, issue, close to each other, two shoots; , one bearing the flower and fruit; the other, drawn out into a wire, a long, tapering, spiral tendril, that twists itself round anything which lies within its reach. Considering, that in this class two purposes are to be provided for, (and together,) fructification and support, the fruitage of the plant, and the sustentation of the stalk, what means could be used more effectual, or, as I have said, more mechanical, than what this structure presents to our eyes? Why, or how, without a view to this double purpose, do two shoots, of such different and appropriate forms, spring from the same joint, from contiguous points of the same stalk? It never happens thus in robust plants, or in trees. "We see not, (says Ray,) so much as one tree, or shrub, or herb, that hath a firm and strong stem, and that is able to mount up and stand alone without assistance, furnished with these tendrils." Make only so simple a comparison.

ing which, different philosophers have given such different opinions; some referring it to the nature of the sap, as De la Hire, others as Darwin, to the living powers of the plant, and the stimulus of air upon the leaves, and of moisture upon the roots. The effect is now shown to be connected with mechanical causes; and there seems no other power in nature to which it can with propriety be referred but gravity, which acts universally, and which must tend to dispose the parts to take a uniform direction. "The direction of the radicles and germens (plumules) is such, that both are supplied with food, and acted upon by those external agents wnich are necessary for their developement and growth. The roots come in contact with the fluids in the ground; the leaves are exposed to light and air; and the same grand law which preserves the planets in their or bits is thus essential to the functions of vegetable life."-Davy's El. Agr. Chem. ii. Ed. p. 32.-Paxton.

as that between a pea and a bean. Why does the pea put forth tendrils, the bean not; but because the stalk of the pea cannot support itself, the stalk of the bean can? We may add also, as a circumstance not to be overlooked, that in the pea tribe these clasps do not make their appearance till they are wanted; till the plant has grown to a height to stand in need of support.

This word "support" suggests to us a reflection upon the property of grasses, of corn, and canes. The hollow stems of these classes of plants are set, at certain intervals, with joints. These joints are not found in the trunks of trees, or in the solid stalks of plants. There may be other uses of these joints; but the fact is, and it appears to be at least one purpose designed by them, that they corroborate the stem; which, by its length and hollowness, would otherwise be too liable to break or bend.

Grasses are Nature's care. With these she clothes the earth; with these she sustains its inhabitants. Cattle feed upon their leaves; birds upon their smaller seeds; men upon the larger: for few readers need be told, that the plants which produce our bread-corn belong to this class. In those tribes, which are more generally considered as grasses, their extraordinary means and powers of preserva tion and increase, their hardness, their almost unconquerable disposition to spread, their faculties of reviviscence, coincide with the intention of nature concerning them. They thrive under a treatment by which other plants are destroyed. The more their leaves are consumed, the more their roots increase. The more they are trampled upon, the thicker they grow. Many of the seemingly dry and dead leaves of grasses revive, and renew their verdure, in the spring. In lofty mountains, where the summer heats are not sufficient to ripen the seeds, grasses abound, which are viviparous, and consequently able to propagate themselves without seed. It is an observation, likewise, which has often been made, that herbivorous animals attach themselves to the leaves of grasses; and, if at liberty in their pastures to range and choose, leave untouched the straws which support the flowers.*

The GENERAL properties of vegetable nature, or properties common to large portions of that kingdom, are almost all which the compass of our argument allows to bring forward. It is impossible to follow plants into their several species. We may be allowed, however, to single out three

With. Bot. Arr. vol. i. n. 28. ed. 2d.

or four of these species as worthy of a particular notice, either by some singular mechanism, or by some peculiar provision, or by both.

I. In Dr. Darwin's Botanic Garden (1. 395, note,) is the following account of the vallisneria, as it has been observed in the river Rhone.-[Pl. XXXV. fig. 1, 2, 3.] "Thev have roots at the bottom of the Rhone. The flowers of the female plant float on the surface of the water, and are furnished with an elastic, spiral stalk, which extends or contracts as the water rises or falls; this rise or fall, from the torrents which flow into the river, often amounting to many feet in a few hours. The flowers of the male plant are produced under water; and as soon as the fecundating farina is mature, they separate themselves from the plant, rise to the surface, and are wafted by the air, or borne by the currents, to the female flowers." Our attention in this narrative will be directed to two particulars; first to the mechanism, the "elastic spiral stalk," which lengthens or contracts itself according as the water rises or falls; secondly, to the provision which is made for bringing the male flower, which is produced under water, to the female flower which floats upon the surface.

II. My second example I take from Withering. (Arrang. vol. ii. p. 209. ed. 3.) "The cuscuta Europœa is a parasitical plant. [Plate XXXVI.] The seed opens and puts forth a little spiral body, which does NOT seek the earth to take root, but climbs in a spiral direction, from right to left, up other plants, from which, by means of vessels, it draws its nourishment." The "little spiral body" proceeding from the seed, is to be compared with the fibres which seeds send out in ordinary cases: and the comparison ought to regard both the form of the threads and the direction, They are straight; this is spiral. They shoot downwards; this points upwards. In the rule, and in the exception, we equally perceive design.

III. A better known parasitical plant is the evergreen shrub, called the mistletoe. What we have to remark in it, is a singular instance of compensation. No art has yet made these plants take root in the earth. Here therefore might seem to be a mortal defect in their constitution. Let us examine how this defect is made up to them. The seeds are endued with an adhesive quality, so tenacious, that, if they be rubbed upon the smooth bark of almost any tree, they will stick to it. And then what follows? Roots springing from these seeds, insinuate their fibers into the woody substance of the tree; and the event is, that a mistletoe S

plant is produced next winter;* of no other plant do the roots refuse to shoot in the ground; of no other plant do the seeds possess this adhesive, generative quality, when applied to the bark of trees.

IV. Another instance of the compensatory system is in the autumnal crocus, or meadow saffron, (colchicum autumnale.) [Pl. XXXVII.] I have pitied this poor plant a thousand times. Its blossom rises out of the ground in the most forlorn condition possible; without a sheath, a fence, a calyx, or even a leaf to protect it; and that, not in the spring, not to be visited by summer suns, but under all the disadvantages of the declining year. When we come, however, to 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 security, and to make up to it for all its defects. The seed-vessel, which in other plants is situated 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 seldom more than a few tenths of an inch long, in this plant extends down to the root. The stiles

in all cases reach the seed-vessel; but it is in this, by an elongation unknown to any other plant. All these singularities contribute to one end. "As this plant blossoms late in the year, and probably would not have time to ripen its seeds before the access of winter, which would destroy them, Providence has contrived its structure such, that this important office may be performed at a depth in the earth out of reach of the usual effects of frost." That is to say, in the autumn nothing is done above ground but the business of impregnation; which is an affair between the anthere and the stigmata, and is probably soon over. The maturation of the impregnated seed, which in other plants proceeds within a capsule, exposed together with the rest of the flower to the open air, is here carried on, and during the whole winter, within the heart, as we may say, of the earth, that is "out of the reach of the usual effects of frost. But then a new difficulty presents itself. Seeds, though perfected, are known not to vegetate at this depth in the earth. Our seeds, therefore, though so safely lodged, would, after all, be lost to the purpose for which all seeds are intended. Lest this should be the case, "a second admirable provision is made to raise them above the surface when they are perfected, and to sow them at a proper dis* Withering, Bot. Arr. vol. i. p. 203, ed. 2d.

† Withering's Botanical Arrangement, p. 360.

tance;" viz. the germ grows up in the spring, upon a fruit stalk, accompanied with leaves. The seeds now, in common with those of other plants, have the benefit of the summer, and are sown upon the surface. 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, [Plate XXXVIII.] an extraordinary American plant, as some late authors have related it: but whether we be yet enough acquainted with the plant, to bring every part of this account to the test of repeated and familiar observation, I am unable to say. Its leaves are jointed, and furnished with two rows of strong prickles; their surfaces covered with a number of minute glands, which secrete a sweet liquor that allures the approach of flies. When these parts are touched by the legs of flies, the two lobes of the leaf instantly spring up, the rows of prickles lock themselves fast together, and squeeze the unwary animal to death."* Here, under a new model, we recognise the ancient 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 sirup, the rows of strong prickles, their position so as to interlock the joints. of the leaves; and what is more than the rest, that singular irritability of their surfaces, by which they close at a touch; all bear a contributory part in producing an ef fect, connected either with the defence, or with the nutrition of the plant.

CHAPTER XXI.

THE ELEMENTS.

WHEN We come to the elements, we take leave of our mechanics; because we come to those things, of the organization of which, if they be organized, we are confessedly ignorant. This ignorance is implied by their name. To say 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 constitution of the elements is not necessary for us. For instance, as Addison has well observed, "we know water sufficiently, when we

Smellie's Phil. of Nat. His. vol. i. p. 5.