Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/262

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called in Englifh the fpoon-hill, from the remarkable figure of its beak, which is different from that of all other birds; be- ing broadeft at the extremity, and terminating in a large rounded, flat procefs. refembling a (hovel ; or, if it were hol- low, a fpoon. Sec Tab. of Birds, N°. az. This bird has been called lucoredius, albardeola, and le'elaer-, and by fome very improperly the pekcanus. It is all over very white, like the ("wan; but that there is fome blacknets in the wings It buiMs in high trees in fome parts of Holland, Ray s Ornithology, p. 212.

PLATESSA, in zoology, a name by which Aufonius and fome other authors have called the pafTer-fifh, or common plaife. Willughby\ Hid. Pifc. p. 96.

PLATFORM (CycL)— All praaitioners are agreed, that no (hot can be depended on, unlefs the piece be placed on a folid platform ; for if the platform (hakes with the nrft hnpulfe ot the powder, it is impoffible but the piece muft likes* ife (hake ; which will alter its direction, and render its mot uncertain. To prevent this accident, the platform is ufually made extreme- ly firm to a confidcrable depth backwards, lb that the piece is not only well lupported in the beginning of its motion, but likewife through a great part of its recoil. However, it is fufficiently obvious, that when the bullet is feparated from the piece, it can be no longer affected by the trembling of the piece of plafor*n\ and by a very eafy computation it will be found, that in a piece ten feet in length, carrying a bullet of 24 lb. and charged with i6lb. of powder, the bullet wilt be out of the piece before it has recoiled halt" an inch ; whence if the platform be fufficiently folid at the beginning of the re- coil, the remaining part of it may be much (lighter, fince its unfteadintfs beyond the firft half inch will have no influence on the direction of the (hot : and hence a more compendious method of conftructing plaifortm may be found out. New Princip. of Gunn, p, 42.

PLA TlASMOS, a word ufed by many authors to cxprefs a fault in pronunciation, owing to a perfon's opening his mouth too wide, and thence (peaking indiftinclly.

PL-ATICORIA, a word ufed by medical writers to exprels a preternatural dilatation of the pupil of the eye, ufually owing to a paralytic diforder,

PLATONIA, in natural hiftory, a name given by the modern Greeks to the prox of Ariftotle, and of other antient writers in that language. This is the cervus platyceros, or broad-horned flag. Some have tranflated this damn, but they are to be un- derwood in this as meaning the dama of their own times, not that of the antients ; that being the ifarus, or chamoy-goat, not any animal of the flag kind, nor by any means ineritinj that title.

PLATYCERCOS ovis, in natural hiftory, the name given by Gefner and fome others to a fpecies of (heep, common. y called ovis laiicauda, or the broad-tailed (heep. The tail of this creature is very thick, broad, and heavy, weighing often thirty pounds. We fometimes fee it brought over hither as a (hew, and find that authors have defcribed the (hape of its tail very inaccurately. Caius, in Gefner, fays it is of the (hape of the tails of other (heep, broad at the infer- tion, and growing gradually fmaller to the end ; but it is ex- actly the contrary of this, being narrowed at the infertion, and growing fomewhat larger and broader to the extremity ; fo that on the whole, it represents a fort of bag or purfe. The creature is not uncommon in iEgypt, Africa, and Ara- bia, and in fome parts of Syria. Ray's Syn. Quad. p. 74. See the article Macroci-.rcos.

PLATYOPHITIALMON, a name given by fome to anti- mony, from its ufe among the ladies of old time, to make their eve brows broad and black

PLATYSTERNuS a word ufed by the old phyficians to exprefs a perfon with a very broad chtft or flernum.

PLATVRYNCHOS, in zoology, a name given by fome to the nafw, or nefe, a frefh water fifh, caught in the Danube, and moft of the large rivers in Germany, and much refembling the chub Gefner 6e Pile. p. 213. See the article Nasus.

PLATYSMA myad s, in anatomy, a name given by Fallopms to one of the mufcles called by Albinus latijfimus colli, and by others quadratic genet.

PLAUSUS, among the Romans, See Acclamation.

PLEA (Cycl)~ Ple, in abatement. See the article Abate- ment, del,

PLEADING. Among the Athenians, an equal time was al- lowed both parties to plead, which was meafured by a water hour-glafs ; .and in order to fee juftice done in this refpect, there was an officer appointed to dirtribute the water to each, whence he was called ephydor. Pit. Arch. Grasc. 1. 1. c. 21 See Ephydor.

PLEASURE-/W, among the antients. See Thalam fgus.

PLECHAS, a word ufed by Hippocrates, to exprefs that region of the body which u terminated backward by the anus, for- ward by the pudenda, and tideways by the hips.

PLECTANj'E, a word ufed by fome to exprefs thecornua uteri, and by others for any plexus of vefiels.

FLECTfV'lNiT./E. See the article Conicthyt don'tts.

PLE'.'TR' iM, a word ufed by fome anatomical writers, to ex- pn fe the rtyioide procefs of the ospetrofum; b ; others for the uvula i and by others for the tongue.

PLE

Plectrum, among the antients, an inflrument ufed in play- ing upon the lyre. We have a defcriptton of it in Mem. Acad. Infcrip, Vol. V. p. 168', 109. See Lyre, Cy<.l.

PLEMMYROS, a word ufed by the old Greek writers to ex- prefs a redundance of humors: its proper fignification is the flowing in of the tide.

PLENNA, a word ufed by fome writers o exprefs any mucous humor.

PLEROsIS, a word ufed by the old Greeks to exprefs the re- pletion or reftoring the body to its natural (fate, after it has been emaciated by fickncfs.

PLESMONE, a word ufed by the antients to fignify plenitude or fatiety.

PLESTYA, in zoology, a name given by Bellonius to a frefh water fifh of the leather-mouthed kind, appearing to be no way efientially different from the more common kind of car- cafius, called by authors carcafjA teriiwn genus. Rafs ichthyogr.- p. 250. See Carcassius.

PLETHORA (Cycl )- Medical writers now ufually diflinguifh four kinds of ^.plethora, r. The fimple plethora, which is that (late of the body in which the blood is too abundant in, quantity, but is as yet of no bad quality. 1. The cacochy- m\ous pleth.ra, which is that where the blood is abundant in quantity, and at the fame time is fubject to a too great thick- nefs, or fome other dyferacy. 3. The plethora ad vafa, whereby the blood, from its over great quantity, renders the vefTels turgid, without any farther ill effect. And, 4. The plethora ad vires, in which there is joined to too great a pleni- tude of the vefiels, a laffitude, and torpor, or numbnefs of the limbs. - The figns of a p lethcra are, 1. A florid conftitution of the body. 2. A tolerable ufe of the non- naturals, a good appetite to food, and a found fleep: this is the cafe while the plet'.ora is fimple and unmoved, but when any commotion happens from without, the figns are inquietude at night, dreams of bleeding, and of wounds from fwords or other weapons, rubi- cund looks in the face, and a general turgefcence of the vefiels, a heavinefs of the limbs, an inaptitude to motion, and diffi- culty of breathing, a vertiginous chforder of the head, a fenfe of a pricking or tingling in the flefh from the flighted: hear, an eafy heating of the body from the weather, a moifture of the eyes, and in hyfteric women a fenfation as if a piece of cold ice were fuddenly laid on fome part of the head.

Perfons m-flfulje5l to a Plethora, are, r. People of fedentary lives, who live high. 2. The younger rather than perfons more advanced in years. 3. The female fex rather than the men. 4. All perfons who have been accuftomed to large eva- cuations, and have haftily fupprefled them. And, 5. Thofe perfons who have fuddenly changed a life of labour or exer- cife to a fedentary one, without making the neceflary changes in the non-naturals.

Prrgrofics from a Plethor a. i. Plethoric perfons are more fubject to difeafes in general than others. 2. They are par- ticularly fubject; to haemorrhages, inflammations, and acute fevers. 3, (he lighter difeafes coming upon perfons of a plethoric habit, are ufually more (lubborn and dangerous than on others. 4. The plethora itfelf can fcarcely be called a dif- eafe, but it is the parent of many difeafes. Chronic dife;fes are with more difficulty cured in plethoric patients than in others becaufe they are always averfe to exercife. 6. A plethoric habit, difturbed by violent motion, by paffions of the mind, or by (timulating medicines, is capable of producing very ter- rible confequenccs. 7. The difeafes arifing from a pletho-a, from flopping fame accuftomed evacuation, are with difficulty cured; and plethoras are more efficacioufly relieved by natural hemorrhages than by any artificial means.

Methodcf cure in a Plethora. A fimple plct-'-ora is eafily removed bv bleeding and gentle exercife, and by a more fpare diet; to thefe may be added, gentle purging once a month. The plethora with acacochymy requires gentle purging, bleed- ing, and cuping, diapbore-ics and diuretics. If a violent commo.ion of the blood happen with a plethora, temperance is to be firft prefcribed, then the ufe of nitre, and crabs-eyes faturated with lemon juice ; and other cooling and alterative remedies. "Junker\ Confpcit Medic, p. 4.

PLEURISY and PERIPNEUMONY fcVJ-Thefe are two difeafes which have fome refemblance in their general fymp- toms, and are thence fometimes miftaken one for the other. They are, however, extremely different in their place of ori- gin, as well as in their feveral fymptoms : the pleurify bein» a ftafis of blood in the pleura ; and the peripneumwy a ftafis of the fame fluid in the lungs They are both attended with an acute, continuous, and inflammatory fever, by means of which nature is labouring to break through the obftruction made by the (lads of the blood in thofe parts.

The fpurious pleurify is to be carefully difianguifhed from thefe two difeafes. In the true pleurify^ or } er pneumony, a pain is ftlt either about or a little below the nipple ; but the fpurious pkurijy generally (hews itfelf higher, ufually about the clavicle. In the genuine difeafes the pains are equal and regular, an- fwering to the pulfe: in the fpurious pleurify they are vague, anil wholly irregular. In the true, they are aifo continual ; but in the fpurious, they have frequent intermiffions and re- miffions. The true have always a cough attending them, and

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