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while, at last they take its nature, and are changed into a similarsubstance.
III. Destruction. Fossils, although the hardest of bodies,yet are subject to destruction, as well as all other created substan-ces. 1 hey are dissolved in various ways by water, air, and thesolar rays; by the rapidity of rivers, violence of cataracts, andeddies, which continually beat upon, and at last reduce to powder,the hardest rocks. The agitations of tin; sea, and lakes, and thevehemence of the waves, excited by turbulent winds, pulverisestones, as evidently appears by their roundness along the shore.Also the chemical actions of various substances destroy the tex-ture, and disunite the parts, of minerals according to their differentaffinities.
Of -the Vegetable Kingdom.
I. Propagation. Anatomy proves, that all plants are organicand living bodies ; and that all organic bodies are propagated froman e,g has been demonstrated. The seeds of vegetables, as wellas of animals, are called eggs; these are different in every differ-ent plant. Many plants, however, push forth from their roots freshoffsets for two or more years. Many may even be propagated bybranches, buds, suckers, and leaves, fixed in the ground, andeven not a few trees. Hence their stems being divided intobranches, may be looked on as roots above ground; for in thesame way the roots creep under ground ; and divide into branches.As a proof of this, a tree will grow in an inverted situation, tin-roots being placed upwards, and the bead downwards, and buriedin the ground ; for then the branches will become roots, and theroots will produce leaves and flowers. The lime-tree may- affordan example, on winch gardeners have chiefly made experiments.Yet this by no means overturns the doctrine, that all vegetables arepropagated by seeds; for in each of these instances nothing vege-.tates but what was the part of a plant, formerly produced fromseed; so (hat, in fact, without seed no new plant is produced.Plants produce seeds; but they are entirely unfit for propagation :unless fecundation precedes, which is performed by an intercoursebetween different sexes. Plants therefore are provided with or-gans of generation, analogous to animals. See Botany . Theseare contained in the llowers. In most flowersthestaininasurrouiulthe pistils, and are of about the same height; but there are manyplants in which the pistil is longer than the stamina ; and in thesethe flowers recline, that the dust may the more easily fall into thestigma, e. g. in the campanula, cowslip, Ac . But when the fecun-dation is completed, the flowers rise again, that the ripe seeds maynot fall out before they are dispersed by the winds. In other llow-ers, where the pistil is shorter, the flowers preserve an erect situa-tion ; when the flowering comes on, they become erect, thoughbefore they were drooping, or immersed under water. When themale flow ers are placed below the female ones, the leaves are ex-ceedingly small and narrow, that they may not hinder the dustfrom flying upwards like smoke; as we see in tin-pine, fir, vew,sea-grape, juniper, cypress, &c. ■ But when in one anil the samespecies one plant is male and the other female, and consequentlymay he far from one another, the male dust is carried in abundanceby the wind from the male to the female; as in the whole class ofDicecia. A more difficult impregnation is compensated by thelongevity of the individuals, and the continuation of life by buds,suckers, and roots. Most flowers expand themselves when thesun shines forth ; whereas when clouds, rain, or evening, come on,they close up, lest the genital dust should be coagulated or ren-dered useless. But when the fecundation is over.- the flowers,never close (hem-elves up. As to the dissemination of seeds afterthey come to maturity, the Author of nature has wisely providedfar this in numberless ways. The stalks and stems raise the fruitabove the ground, that the winds, shaking them, may disperse fiiro;f the ripe seeds. Most of the pericurpia are shut at top, thatthe seeds may not fall before they are shaken out hv stormy winds.Wings are given to many seeds, by the help of which they flv farfrom the mother-plant, and often overspread a whole country.These wings consist either of a down, as in most of the compositeflowered plants; or of a membrane, as in the birch, alder, ash, Ac .Hence woods, which happen to he consumed by lire or any otheraccident, are soon restored by new plants disseminated by thesemeans. Many kinds of fruit are endued with a remarkable elasti-city, by the force of which the ripe pericurpia throw the seeds to a
great distance; as the wood-sorrel, the spurge, the phyllanthus, thedittany, Ac . Other seeds or pericurpia are rough, or providedwith hooks ; so that they are apt to stick to animals that pass bythem, and are thus carried to their holes, where they are both sowuand manured, and therefore the plants of these seeds grow whereothers will not; as hounds-longue, agrimony, Ac . Bu ries andother pericurpia are allotted for aliment to animals; hut. while theyeat the pulp they sow the seeds ; tor they either disperse tln-ni atthe same time ; or, if they swallow them, they always come outunhurt. By means of the sea, lakes, and rivers too, seeds are oftenconveyed unhurt to distant countries. Various oilier ways inwhich nature provides for the dissemination of plants, are pointedout by Limueus in an Oration concerning the augmentation of thehabitable earth.
II. Preservation. The great Creator of all things decreed,that the whole earth should he covered wiih plants, and that noplace should he void, none barren. But since all countries havenot the same changes of seasons, and every soil is not equally fit foeevery plant; he therefore, that no place should he without some,gave to every one of them such a nature, as might be chieflyadapted to the climate: so that some of them can hear an intensecold, others an equal degree of heal; some delight in dry ground,others in moist, Ac . The Alpine plants live only in high anilcold situations ; and therefore often on the Alps of Armenia ,Switzerland, the Pyreneans, Ac . whose tops are equally coveredwith eternal snows as those of the Lapland Alps, plants ot the samekind are found, ami it would he in vain to seek for them anywhere else. The Alpine plants blow, and ripen their seeds, veiyearly, Jest the winter should steal upon ihem on a sudden, anddestroy them. Our northern plants, although they are extremelyrare every where else, yet are found in Siberia , and about Hudson’sBay ; as the arbutus, bramble, winter-green, Ac . Plants impatientot cold live within the torrid zones; hence both the Indies, notrwithstanding their distance, have plants in common. 'The Capeof Good Hope produces plants peculiar to itself; as all the mesem-bryanthema, and almost all the species of aloes. Grasses, themost common of all plants, can hear almost any temperature, forthey above all plants are necessary for the nourishment of cattle;and tiie same thing is observed of our most common grains. Thusneither the scorching sun, nor the pinching cold, hinders anycountry from having its vegetables. Nor is there any soil whichdoes not bring forth many kinds of plants. '1 lie pond-weeds, thewater-lily, and lobelia, inhabit I he waters. The- fluviales, fur: i,conferva.-, cover the bottoms of rivers, and seas. T he sphagna tillthe marshes. The brya clothe the plains. The driest woods,and places scarcely ever illuminated by the rays ot the sun, areadorned with the hvpna. Nay , stones and the trunks of trees arenot excepted, for these are covered with various kinds of liver-wort. 'Pile desart and most sandy places have their peculiar trees andplants; and as rivers or brooks are seldom found there, we cannotwithout wonder observe that many of them distil water, and bythat means afford the greatest comfort both to man and beast thattravel there. 'Phus the lillandsia, which is a parasitical plant, andgrows on the tops of frees in the desalts ot America , has its leavesturned at the base into the shape of a pitcher, with the extremityexpanded ; in these the rain is collected, and preserved for thirstymen, birds, and beasts. Plants often by their very structure con-tribute remarkably both to their own preservation and that ofothers. But the wisdom of the Creator appears no where morethan in the manner of the growth ol tn es. for as their roots de-set nd deeper than those of other plants, provision is made, that theyshall not rob them too much of nourishment ; and a stym notabove a span in diani. ter often shoe’s up its branches very high ;these bear mane thousand buds, each of which is a plant, with itsleaves, flowers, and slipuhe. Now if all these grew upon the plain,they would take up a thousand turn's as much space as the treedoes; and in this case there would scarcely he room in all theearth for so many plants as at present the trees alone afford. Be-sides, plants that shoot up in this way are more easily preservedfrom cattle ; and their leaves falling in autumn cover the plantsgrowing against the rigour of the winter ; ami in summer theyafford a piea.dng shade, not only to animrls, hut to plants, againstthe intense heat of the sun. Trees imbibe water from the earth ;which water does not circulate again to the rout, but being dis-persed, like small rain, by the transpiration of the leaves, moistens