Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/260

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The characters of this genus are thefe : The cup Is an erect ■very fhort perianthium, divided into four at the edges, and remaining alter the flower is fallen. The flower confifts of one petal, in form of a cylindraceo-gtobofe tube, with the limb cut into four parts; the fegments being depreffed, of an oval figure and pointed; the ftamina arc four extremely long, erect capillary filaments ; the anthers are oblong, flatted, and lean upon the ftamina; the gerraen of the piftil is of an oval figure; the ftyle is (lender, and but of half the length-of the ftamina; and the ftigma is fimple ; the fruit is an oval cap- fule, containing two cells, parting horizontally ; the feeds are numerous, and oblong. Linnai Genera Plant, p. 46. PLANTE-'i.vr, in natural hiftory, the name of an herb fent over from China, where it is called hlatfaotonetchom ; that is to fay, a plant which at a certain time of the year changes into a worm. The Ch'mefe fay, that this is a plant during the fummer feafon ; but that in winter Its Italic dies, and the root becomes a worm. Mr. Reaumur has well obferved, that in the prefent improved ftate of natural knowledge, we can give no credit to fuch marvellous accounts ; and of the roots fent over to the Academy at Paris, it appeared, that only a certain part of each was to undergo this change : this, however, if true, was no lefs a marvel than that the whole mould.

Father Parenin, who fent it to France, obferves, in his ac- count of it, that it was a very fcarce plant even in China ; being, found only at the palace of Pekin there, where alfo it was not native, but brought. from the mountains of Tibet, and (bme other places on the confines of the Chinefe domi- nions. This father had never (een the leaves or flowers of the plant, but only its roots, whicn were in high efteem their, not only becaufe of their miraculous changes, but from there poflefiing the virtues of the famous ginfeng; but with thir advantage, that the ufe of them was not fubject to be attend- ed with thofe hemorrhages which frequently affected the per foas who take large quantities of that famous root. The roots of this planta-ver are ufually about a quarter of an inch thick, and from an inch to three inches in length ; but there are much larger in the places where they grow. Thefe roots had nothing particular in their figure or appear- ance ; but with thefe the father fent fome of thofe which were fuppofed to be changed into worms, concerning which he obferved, that nothing could more exactly exprefs a worm or caterpillar ; the head, the eyes, the feet, and the mouth, being all plainly diftinguifhable, as well as the feveral folds and cuttings in of the body. This account was found to be per- fectly true ; but the miftake was the want of proper accuracy in the obfervation ; for this body, which was fuppofed to be the root transformed, had in reality never been any part of the plant, but was found to be really and truly a caterpillar. This was one of the under-ground kind, or at leaft of thofe which go into the ground to pafs their transformation : of thefe we have a great many different fpecies in all parts of Europe, and fome of them, when they are entering into their nymph ftate, have a cuftom of fattening themfelves to the roots of plants. Of this kind was the Chinefe infect, which when the time of its change approached, always felected the roots of this plant as of a proper fixe and dimenfion for its p'urpofe ; and gnawing off the end hollowed away the ftump, fo as to introduce its tail into the cavity ; where it remains covered with the bark of the root, which fo nicely joins to it, that people who obferve it in a (light way cannot but mif- take it to be a part of the root, or the remainder of the root, a continuation of its body. The more accurate naturalifts will, however, eafy diftinguifli The vegetable fibre?, which make up the root from the animal ones of the caterpillar ; and to an eye acculfomed to fuch refearches, the nice joining of the tail to the remainder of the root will eafily difcover it- felf. Mem. Acad. Par. 1720. PLANTKD-c'M?, in the manege. See Hair, Cycl. PLASHING, a term ufed by our farmers to exprefs an opera- tion performed at certain times upon their qiiickiet-hcdges, in order to affift their growth and continuance. This operation is performed fometimes in October, but more ufually in Fe- bruary; and this is by much the better feafon for it. Sup- pofe a hedge to be of twenty or thirty years growth, and full of old Hubs as well as young fhoots, this is the kind of hedge that requires plajbmg raoft of all.

The old flubs muft be cur, oft* within two or three inches of the ground, and the beft and longeft of the middle fized fhoots muft be left to lay down. Some of the ftrongeft of thefe muft alfo be left to anlwer the purpofe of ftakes. Thefe are to be cut off to the height at which the hedge is intended to be left ; and they are to ftand at ten foot diftance one from another : when there are not proper fhoots for thefe at the due diftances, their places muft be fupplied with common ftakes of dead wood. The hedge is to be firft thinned, by cutting away all but thofe moots which are intended to he ufed either as ftakes, or the other work of the phjhing : the ditch is to be cleaned out with the fpade: the ditch muft be now dug as at firft, with Hoping fides each way ; and when there is any cavity on the bank on which the hedge grows, or the earth ha:; been wfafhedfeway from the roots of the fhrubs, it is to be made good !.y facing it, as they exprefs it, with the

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mould dug from the upper part of the ditch ; all the reft f the earth dug out of the ditch is to be laid upon the top of the bank, and the owner fliould look carefully into it that this be done ; for the workmen, to fpare themfelves trouble, are apt to throw as much as they can upon the face of the bank; which being by this means overloaded, is foon warn- ed off into the ditch again, and a very great part of die work undone again, whereas what is laid on the top of the bank always remains there, and makes a good fence of an indifferent hedge.

In the pkjhingjhe quick, two extremes are to be avoided ; thefe are, the laying it too low, and the laying it too thick : this makes the fap run all into the fhoots, and leaves die plafies without fufncientnourifhmcnt; which, with the thick- nefs of the hedge, finally kills them. The other extreme of laying them too high, is equally to he avoided ; for this car- ries up all the nourifliment into the flajhes, and fo makes the moots fmall and weak at the bottom, and, confequently, the hedge thin. This is a common error in the north of Eng- land. The beft hedges made any where in England, are thofe of Hertfordfhire ; and they are plajlied in a middle way be- tween the two extremes, and the cattle are by that prevented both from croping the young fhoots, and from going thro'j and a new and vigorous hedge foon forms itfelf. When the fhoot is bent down that is intended to be plafoed, it muft be cut halfway thro' with the bill : the cut muft be given Hoping, fomewhat downwards, and then it is to be wound about the ftakes, and after this its fupcrfluous bran- ches are to be cut off, as they ftand out at the fides of the hedge. If for the firft year or two the field where a new hedge is made can be ploughed, it will thrive the better for it ; but if the ftubs are very old, it is beft to cut them quite down, and to fecure them with good dead hedges on both fides, till the fhoots are grown up from them ftrong enough to plajlj ; and wherever void fpaces are feen, new fets are to be planted to fill them up. A new hedge raifed from fets in the common way, generally requires plajhing about eight or nine years after. Mortimer's Hufbandry, p. 10. PLASTER (Cfd:) — Plaster, in pharmacy, an external ap- plication of a harder confiftence than our ointments : thefe are to be fpread according to the different circumftances of the wound, place, or patient, either upon linnen or leather. If the part upon which they are to be laid be naturally hairy, it muft be fhaved ; but that they may flick the better, the na- tural fhape of the part muft he confulted, and ihepla/ler fpread and formed accordingly, either round, fquare, triangular, elleptical, in a lunar form, or in fhape of the letter T. Some alfo are divided at both ends, and others are perforated in the middle; thefe laft are of frequent ufe in fractures attended with a wound ; for by this contrivance the wound may be cleanfed and dreffed without removing .the plajier. Thefe plajlers are of different forms, according to the part they are laid on ; but they are ufually fquare, or round ; and indeed there is almoft no part of the body which a plajier of one of thofe forms may not be made to ferve for, if it be notched about the edges with a pair of fciflers.

The ufes of plajhrs are various ; they are ferviceable in fe- curing the drefhngs, they alfo forward the maturation of the pus, agglutinate and heal wounds, unite broken bones, heal burns, afluage pain, and ftrengthen weak parts. Hei/ler's Surg. p. 18. Plaster of Part!. The method of reprefenting a face truly in plajier of Paris, is this : The perfon whofe figure is de- fined is laid on his back, with any convenient thing to keep or? the hair. Into each noftril is conveyed a conical piece of ftiff paper, open at both ends, to allow of refpiration. Thefe tubes being anointed with oil, are fupported by the hand of an aftiftant ; then the face is lightly oiled over, and the eyes being kept ftiut, alabafter frelh calcined, and temperea to a thinnifli confiftence with water, is by fpoonfuls nimbly thrown all over the face, till it lies near the thicknefs of an inch. This matter grows fenfibly hot, and in about a quarter of an hour hardening into a kind of ftony concretion ; which being gently taken off reprefents. on its concave furface, the mi- nuteft part of the original face. In this a head of good clay may be moulded, and therein the eyes are to be opened, and other neceiFary amendments made. This fecond face being anointed with oil, a fecond mould of calcijied alabafter is made, confiding of two parts joined lengthways along the ridge of the nofe ; and herein may be caft, with the fame matter, a face extremely like the original. Boyle's Works, abr. Vol. I. p. 132.

If finely powdered alabafter, or plajier of Paris, be put into a bafon over a fire, it will, when hot, ailume the appearance of a fluid, by rolling in waves, yielding to the touch, fteam- ing, cifr. all which properties it again lofes on the departure of the heat; and being thrown upon paper, will not at all wet it, but immediately difcover itfelf to be as motionlels as before it was let over the fire ; whereby it appears, that a heap of fuch litde bodies, as are neither ioheri- cal, nor otherwife regularly fhaped, nor fmall enoug to be below the difcernment of the eye, may, without iu- fion, be made fluid, barely by a fufficiently flrong and va- rious agitation of the particles which compofc it; and, mor