Page:Cyclopaedia, Chambers - Volume 2.djvu/411

 PHL

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PHL

'The true 'Philtres are thoft fuppofed to work their Effect \)y fome natural and magnetical Power.

There are many grave Authors who believe the Reality of thefe Philtres $ and alledge matter of Fact in Confirmation of their Sentiments: among the reft, Van-Helmont, who fays, that upon holding a certain Herb in his Hand for fome time, and taking afterwards a little Dog by the Foot with the fame Hand j the Dog follow'd him wherever he went, and quite defertcd his former Matter.

He adds that philtres only demand a Conformation of Mumia ; and on this Principle accounts for the Phenomena of Love tranfplanted by the Touch of an Herb ; for, fays he, the Heat communicated to the Herb, not coming alone, but animated by the Emanations of the natural Spirits j deter- mines the Herb towards the Man, and identifies it to him : Having, then received this Ferment, it attracts the Spirit of the other Object magnetically, and gives it an amorous Mo- tion. See Mumia and Transplantation.

But this is mere Cant ; and all Philters, whatever Facts may be alledgM, are mere Chimera's.

Naturalilts afcribe an Effect fomewhat of Kin to that of a Philtre to Cantharides, taken inwardly ; thefe, 'tis true, tend to excite love, or rather Lull; but 'tis Lull in the General, not determin'd to any particular Object 5 and they do it no otherwifc than by irritating the Fibres of the Nerves and Muf- cles by whofe Action the Emijfw Seminis is effected. See Cantharides.

The Word 'Philtre is form'd from the Greek tptxUtv to love.

PHIMOSIS, in Medicine, a Difeafe of the 'Penis, where- in the Preputium is glued, or ftrongly conftringed upon the Glans * fo as not to be capable of being drawn back, to un- cover the Glans. See Glans and Prepuce.

The Word is alio ufed for a Difeafe of the Eyes, wherein the Eye-lids are fo bound together by the Mediation of fome glutinous Matter, as not to be open'd.

The Word is Greek, and properly fignifies a Ligature with Packthread, ^fn»m(, denoting Packthread.

Sometimes a Phimofis conceals Shankers on, or about the Glans • and fometimes is fo violent as to prevent the flowing out of 'the Matter, whence it caufes an Inflammation or Mor- ficationofthePart. '" ,.„ _, ,

The Cure of a Paraphimosis in no ways diners from that ot a t phimcjis i except in the Ufe of Injections ; and in both Cafes, 5f they ftiU prove obftinate, the Prepuce mufl: be cut, in or- der to reduce it to its natural State or Situation.

PHLEBOTOMY, in Medicine and Chirurgery, "Bleeding 5 or the Art or Operation of letting Blood. See Blood. TheWord is compounded of the Greek pjb4, Vein, and li^vuv,

'phlebotomy is a Manner of Evacuation of the utmofi Im- portance in Medicine, an Idea of its Effects, with the Reafon of its Ufe may be conceiv'd from what follows.

'Tis evident the Blood thrown out of the Heart, while it ftrikes upon the antecedent Blood, and drives it forwards, transfers to it Part of its own Motion, and is therefore fo much retarded in its own Motion. Hence, if Blood be drawn out of the Bafilic Vein of the right Arm 5 the fucceed- ing Blood, or that carried by the axillary Artery, or right Subclavian, will be lefs hinder'd in its Motion, than it was before that Vein was open'd ; for Part of the Blood being taken away by the opening of that Vein, there remains be- hind a leffer Quantity in the axillary Vein, or lefs is contain- ed between the farther Extremity of the axillary Artery and the Heart than was before : therefore the Blood being let out by theVein, the Remainder in the Artery will be lefs impeded in its Motion than before. See Pulse.

Hence the Blood of that Artery which communicates with the Vein that is opened, will flow with a greater Velocity after the Aperture is made than before. Consequently, while the Blood is flowing out of the Vein in the Arm, that thrown out of the Heart into the Aorta, will find lefs Refiftance in the afcending Trunk, than in the Defcending; and will there- fore flow falter in the Afcending, than in the defcending Trunk : And thence too it will find lefs Refiftance in the right Subclavian Artery than in the left.

Laflly. it hence appears, that the Blood being let out of a Vein in the right Arm, the remaining Blood in the right ax- illary Artery runs with a greater Velocity into the Artery of that Arm that is contiguous to it, than through the thoracic Artery, or the right Scapulary, which is likewife contiguous to it - beeaufe, when the Blood is not fuppofed to be drawn out from any Vein correfponding to the thoracic Artery, or into which this dfcharges itfelf, there is proportionally a greater Impediment to the Motion of the Blood in the thora- cic Artery, than in that of the Arm. But beeaufe the Velo- city of the Blood in the fubclavian Artery, or the right Axilla- ry, is greater than in the Left ; the Velocity in the right Tho- racic will alfo be greater than in the left thoracic Artery. Hence it is manifeft, that the Blood being let out of a Vein in the right Arm 5 the greater! Velocity of the remaining Blood will be in the Artery of that Arm, beeaufe it immediately empties its Blood into the Vein that is opened 3 and the next

greateft Velocity will be in the thoracic Artery, or Scapula- ry of the fame Side, going out from the axillary Artery. But the Velocity ot the Blood will be far lefs in the brachial Axillary, and thoracic Artery on the left and oppofite Side * and leait of all in the Arteries arifing from the defcending Trunk of the Aorta.

On this View it may eafily be gathered, what is to be done in the feveral Circumftances of 'Blood-letting; For inftance, if we would prevent the increafe of any Humour from the Blood ftagnating in the left Leg, or bring it about, that as little Blood as poflible, mould flow to that Leg in any given fpace of Time ; firft, Blood is to be taken from the Arm or Leg of the right Side, beeaufe this is truly making what is call'd a Ke-vulfion.

Again, if Blood be drawn away on the fame Side, and from fome Vein that receives the Blood from a Branch of that Trunk which tranfmits it to the fwell'd Part 5 it will oc- cafion a greater Derivation of Blood to that Limb.

As to what relates to the whole Habit ; in all Lentors and Vifcidities, if there be a due Strength and Elafticity remain- ing in the Solids, 'Phlebotomy will make the remaining Blood circulate the falter, and become thinner and warmer ; but in a Plethora, from Debauch, and too large Quantities of fpirituous Nourishment, or froma Diminution of Perfpiration, where the Blood yet retains its natural Fluxility, 'Phlebotomy will make the remaining Mafs circulate flower, and become cooler.

In the former Cafe, a Diminution of the Refiftance in the Blood- Veffels, will increafe the contractile Powers of thofe Veffels, and make them beat falter, and circulate their Con- tents with greater Velocity 5 but in the latter Cafe a Diminu- tion of the Quantity of a fpirituous Blood will leflen the Quantity of Spirit iecrered in the Brain, the Confetmence of which will be that the Heart and Arteries will not contract fo often nor fo ftrongly as before, and therefore the Blood will move flower, and become cooler. See Heart and Artery.

And on thefe Things depend the whole Doctrine oiSlocd- letting- See Evacuat ion.

PHLEGM, in Chymiftry, is an aqueous andinfipid Fluid, fuppofed to be found in all natural Bodies j coinciding with what the other Philofopherscall Water. See Water.

'phlegm makes the 4th of the Chymical Elements, or Ele- mentary Principles. See Principle and Element.

In the Diftillation of Vinegar, as alfo of all Minerals and inodorous Vegetables, 'Phlegm comes out firfl: 3 in that of Wine laft. See Distillation.

This Phlegm is fuppofed to be the common Vehicle and Diluter of all i'olid Bodies j and in proportion to its Quantity in the Mixture, are the other Parts more languid and difabled in their Attractions ; yet, on the Chymiits Principles, Phlegm fhou'd be a Principle of Adtion ; as being necefiary to the Diifolution of the Salt in Bodies, without which the Salt mult remain inactive. See Salt.

It is much to be queition'd whether this Phlegm can ever be procured without any Mixture of other Matters 5 that which has the leaft rauft come neareft to the Nature of a Prin- ciple ; and on that account Rain-water ftiou'd afford it molt.

Phlegm, Soerfraave obferves, drawn by Diftillation from Vegetables, does always carry with it fome what of the Smell of the Vegetable, which it derives partly from the Oil, and parrly from the Spirit refiding therein. The fame Phlegm, by frequently reiterated Diitillations, lays afide mofl; of this Smell, and approaches nearer to pure Water, but never be- comes perfectly i'ueh. Add, that the pureft diftill'd Water, if expofed a few Days to the Sun, is much changed, and render'd turbid.

That Phlegm is not an elementary Body, Mr. Boyle argues from its different Powers and Properties ; the Phlegm of Wine, and moft Liquors, have Qualities that make them dif- fer from mere Water, and from one another ; the Phlegm of Vitriol that Author obferves is an effectual Remedy againit. Burns - and a valuable Noftrum for difcufling hard Tumours ^ that of Vinegar will extract a Saccharine Sweetnefs out ot Lead, and even diflolve Corals with long Digeftion 5 and that of Sugar of Lead, is faid to diflolve Pearls.

In Effect, the Characters which ferve to denominate a Flu- id, Phlegm, or Water, among the Chymiits, are Infipidityand Volatility 5 yet, Qukk-filver has all thefe, which no Body pre- tends to be Phlegm. Add, that it appears from feveral Expe- riments, that Water itfelf, by repeated Diftillations, may be converted into Earth. Yet Water, the fame Author obferves, has a much fairer Pretence to be an Element, than any of the tria prima.

Add, that as to the Qualities which occafion that Name to be given any vifible Subftance, viz. its being Fluid, Infipid, and inodorous ; we have never yet feen any of thefe fepara- ted Subftances, which the Chymifts call Phlegm, perfectly deftitute both of Tafte and Smell.

Common Salt, and feveral other ialine Bodies diftilled ever fo dry, will each yield a large Quantity of Phlegm 5 which can no other way be accounted for, but from this, that among the various Operations of the Fire, on the Matter of a Concrete, feveral Particles of that Matter are reduced to a

Shape