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 dg2 B O' T particular part, but are diffufed through the whole plant. The Diadelphia clais forms the jyth natural order. This clafs comprehends above 500 fpecies; and, as was obferved above, the feeds of every one of them are efculent, the leaves afford excellent pafture for cattle, and not one of them have any poifonous quality. The Svngenesia clafs, or 21ft natural order, contains a very great number of fpecies. The virtues of fome plants belonging to this clafs are faid to differ confiderably. The bardana, carlina, tuflilago, arnica, cichorium, fcorzonera, taraxacum, <bc. are fuppofed to be deobftruent, and are kept as fuch in the {bops. But the greatefl number of them are bitter and ftomachic; e. g. the abfmthium abrotanum, artemifia, fantolina, balfamita, tanacetum eupatorium, matricaria, chamomilla, acmella, verbefina, <bc. The G y n a nn r. 1 a D1 an d r t a, Or 4th natural order, are faid to excite venery; e. g. the orchis, fatyrium, ferapias, herminium, ophrys, epidendrum, <bc. The roots of thefe are ufed with this intention by practitioners. The Amentacete Acifolije, or 15th natural order, are refinous; e. g, the pious, abies, juniperus, cupreffas, <bc. They are all warm Simulants and diuretics. The virtues of the CRYProGAMiAclafs,which comprehends the 61 ft, 62d, 63'd, and 64th natural orders, are moftly of a fufptcious nature. Hardly any of the filices are efculent; their fmell is difagreeable, and they are faid to kill worms. All the mufei, except the lichen iflandicus, are improper for food. Some of the fungi are eat; but they arc a very dangerous food. Plants which have their nedtaria feparate from the flowers, are commonly poifonous; e. g. the epimedium, nigella, aquilegia, aconitum, monotropa helleborus, isc. Thofe plants which are called lattefcent, from their oozing out a whitifli juice upon being wounded, are generally poifonous; e. g. the euphorbia, papaver, periploca, cynanthum, &c. But thofe which are called fsmiflofculofdc by Tournefort, are of a milder nature; t.g. ladtuca, hieracium, crepis, leontodon, <bc. Befides natural clafles and orders, which prefuppofe fome acquaintance with botany, we are provided with other means of difeovering the general qualities of plants. The feilfations of fmell and tafte give us fome intimation of the nature and qualities of plants. An agreeable tafte or fmell is feldom accompanied with noxious qualities • on the other hand, when ihefe fenfes are difagreeably affefted, the qualities are generally more or lefs noxious, being either purgative, emetic, or poifonous. Plants that have a fweet tafte are generally nutritive; thofe that have a fait tafte are warm and ftimulant. Plants of an acrid tafte are corrofive; but, when deprived of their acrimony by drying, fome of them become fit for food. Bitter plants are alkaline, ftomachic, and fometimes of a fufpicious nature. Acid plants are cooling, and allay third; but thofe of an auftere tafte are aftringent. Even the colour and afpeA of plants throw fome light upon their nature Flowers, or fruit of a red colour are generally acid. Yellow flowers indicate a bitter tafte. Plants that have green flowers are crude; thofe of a pale

ANY. colour are commonly infipid; thofe of a white colour are generally fweet; and thofe whofe flowers have a gloomy and difmal afpeA, are moftly poifonous. Thefe examples naturally fuggeft the following obfervations.—The Creator of the univerfe hath endowed us with fufficient abilities for inveftigating thevirtues of plants, and applying them to the cure of difeafes and other ufeful purpofes, even on the fuppofition that we were obliged to afeertain the virtues of every Angle plant by experiments. But this labour, though praAicable in a courfe of years* and under proper regulations, is greatly abridged. The information afforded by the fenfes is confiderable. Our inquiries are ftili further aflifted by the general diftribution of vegetables into tribes and families. The mutual relation and conneAion of thefe tribes depend not upon fancy or conjeAure: The relations are fo ftrongly marked by the fimilarity of their flowers, fruit, and fenfible qualities, that they are confpicuous at firft fight. A perfon unacquainted with medicine, from this view of the virtues of plants, will be apt to imagine, that botany is the only road to that fcience; and of courfe that every phyfician muft either be a good botanift, or a bad praAitioner. The thought is natural, and, with fome limitation, not unjuft. The common praAice of phyfic does not require an extenfive {kill in the virtues of plants. A certain number of vegetables and other fubftances are kept in the {hops, and recommended for particular purpofes in difpenfatories and books of praAice. It is the bufinefs of the praAitioner to have a general acquaintance with thefe, and to preferibe them according to the cuftom of the times. But inveftigations into the nature and properties of fimples or drugs, require more time than can be beftowed by men of bufinefs. Whenever any fcience is converted into a trade, and the ftudy of it confined to people who muft live by it, there is little profpeA of improvement. This has been the fate of phyfic. Every body difpenfes medicines; but few are none inquire into their virtues. Some valuable medicines have been difeovered, But by whom? Not by phyficians,' but by favages, old women, priefts, and chymifts. Until, therefore, the ftudy of phyfic be confidered as a branch of natural hiftory, and cultivated by people who have time to make experiments, the fcience muft continue to be vague, defultory, and limited in its utility. Botany has always been confidered as a branch of natural hiftory. But, as was formerly obfervCd, the ufeful part of it hath been too much negleAed. The virtues of plants may be fuccefsfully inveftigated without an extenfive knowledge in all the branches of the medical art. To propagate a tafte for inquiries into the nature and properties of vegetables, would therefore lay the moft folid foundation for improvements in medicine. 3. Art s.—The application of the qualities of vegetables to the various mechanical arts affords a moft extenfive field for ufeful obfervation. There are few plants, however different in their nature, but are found.by experience to be not only the moft proper, but effentially neceffary, in fome particular art or employment. The qualities which render vegetables fo generally applicable to mechanical employments are principallySoftnefs thefe: