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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. 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 antheræ 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, or out of the reach of the usual effects of frost." But then a new difficulty presents itself. Seeds, though perfected, are known not to vege. tate 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 distance :” viz. the germ grows up in the spring, upon a fruit-stalk, accompanied with leaves. The seeds
in with those of other plants, have the benefit of the summer, and are sown upon the surface. The order of
* Withering, '
ubi supra, p. 360.
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 diongea muscipula, an extraordinary American plant, as some late authors have related it: but whether we be yet enough aequainted 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 organised body to which they belong. The attracting syrup, the rows of strong prickles, their position so as to interlock, the joints of the leaves; and, what is more than the rest, that sin. gular 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.
When we come to the elements, we take leave of our mechanics ; because we come to those things, of the
* Smellie's Phil. of Nat. Hist. vol. i. p. 5.
organisation of which, if they be organised, 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, know water sufficiently, 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 made: for the constitution, and the constituent parts, of water, appear in some measure to have been lately discovered ; yet it does not, I think, appear, that we can make any better or greater use of water since the discovery, than we did before it.
We can never think of the elements, without reflecting upon the number of distinct uses which are consolidated in the same substance. The air supplies the Jungs, supports fire, conveys sound, reflects light, diffuses smells, gives rain, wafts ships, bears up birds. 'Eg vòaroç ta mavta : water, besides maintaining its own inhabitants, is the universal nourisher of plants, and through them of terrestrial animals; is the basis of their juices and fluids; dilutes their food; quenches their thirst, floats their burdens. Fire warms, dissolves, enlightens ; is the great promoter of vegetation and life, if not necessary to the support of both.
We might enlarge, to almost any length we pleased, upon each of these uses; but it appears to me almost sufficient to state them. The few remarks, which I judge it necessary to add, are as follow:
1. Air is essentially different from earth. There
appears to be no necessity for an atmosphere's invesa ting our globe ; yet it does invest it: and we see how many, how various, and how important are the purposes which it answers to every order of animated, not to say of organised, beings, which are placed upon the terrestrial surface. I think that, every one of these uses will be understood upon the first mention of them, except it be that of reflecting light, which may be explained thus :- If I had the power of seeing only by means of rays coming directly from the sun, whenever I turned my back upon the luminary, I should find myself in darkness. If I had the power of seeing by reflected light, yet by means only of light reflected from solid masses, these masses would shine indeed, and glisten, but it would be in the dark. The hemise phere, the sky, the world, could only be illuminated, as it is illuminated, by the light of the sun being from all sides, and in every direction, reflected to the eye, by particles, as numerous, as thickly scattered, and as widely diffused, as are those of the air.
Another general quality of the atmosphere is the power of evaporating fluids. The adjustment of this quality to our use is seen in its action upon the sea. In the sea, water and salt are mixed together most intimately ; yet the atmosphere raises the water, and leaves the salt. Pure and fresh as drops of rain descend, they are collected from brine. If evaporation be solution (which seems to be probable), then the air dissolves the water, and not the salt. Upon whatever it be founded, the distinction is critical; so much so, that when we attempt to imitate the process by art, we must regulate our distillation with great care and nicety, or, together with the water, we get the bitterness, or, at least, the distastefulness, of the marine substance: and, after all, it is owing to this original elective power
in the air, that we can effect the separation which we wish, by any art or means whatever.
By evaporation, water is carried up into the air; by the converse of evaporation, it falls down upon the earth. And how does it fall ? Not by the clouds being all at once re-converted into water, and descending like a sheet; not in rushing down in columns from a spout; but in moderate drops, as from a colander. Our watering-pots are made to imitate showers of rain. Yet, à priori, I should have thought either of the two former methods more likely to have taken place than the last.
By respiration, flame, putrefaction, air is rendered unfit for the support of animal life. By the constant operation of these corrupting principles, the whole atmosphere, if there were no restoring causes, would come at length to be deprived of its necessary degree of purity. Some of these causes seem to have been discovered; and their efficacy ascertained by experi ment. And so far as the discovery has proceeded, it opens to us a beautiful and a wonderful economy. Vegetation proves to be one of them. A sprig of mint, corked up with a small portion of foul air, placed in the light, renders it again capable of supporting life or flame. Here, therefore, is a constant circulation of benefits maintained between the two great provinces of organised nature. The plant purifies, what the animal has poisoned ; in return, the contaminated air is more than ordinarily nutritious to the plant. Agitation with water turns out to be another of these restoratives. The foulest air, shaken in a bottle with water for a sufficient length of time, recovers a great degree of its purity. Here then again, allowing for the scale upon which nature works, we see the salutary effects of storms and tempests. The yeșty waves which confound the