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P E R 
P E R 
plant into any fufliciently-capacious glafs veflel; when 
the fluid which exudes will trickle down the Tides of the 
glafs in great abundance, efpecially if the experiment be 
made in fun-fhine. The liquor thus obtained is of a clear 
watery nature, fcarcely diftinguifhable to our fenfes, or 
to our chemical enquiries, from the Tap of the fame plant, 
whatever it may be, procured by wounding its branches 
before the foliage expands. This, which may be termed 
the infenfible perfpiration of plants, becomes in fome cafes 
fenfible; a,s when it runs down, like a flight fliower, from, 
willow or poplar trees, in hot funny weather; or when it 
collefts in drops on the leaves of plaintain-trees in a 
Hove. 
Hales and others have made experiments to afcertain 
the quantity of infenlible perfpiration in various plants. 
The great annual fun-flower was found to perfpire about 
feventeen times as much as the ordinary infenfible perfpira¬ 
tion of the human (kin. The Cornus mafcula, or corne¬ 
lian cherry, is faid to difcharge, in twenty-four hours, as 
much fluid as is equal to twice the weight of the whole 
fhrub. Succulentleaves perfpire much (lower than others, 
though they abforb in a far more rapid proportion. 
This watery perfpiration is the only excrementitious 
difcharge of the vegetable body. The fap, being carried 
up into the leaves, where it is afted upon by air and light, 
for the moft important purpofes, yields thofe various and 
liighly-curious fecretior.s, which, being carried down into 
the bark, afford matter for the increafeof the tree, as well 
as for the manifeltation of its various qualities. The great 
bulk of the fap which remains, as it does not return to 
the root, like the blood of animals to their heart, can be 
difpofed of no otherwife than by a copious evaporation. 
Dr. Darwin was of opinion that this watery perfpiration 
rendered a further fervice to the plant, by being aided 
upon by light, fo as to give out oxygen, which was imme¬ 
diately abforbed by the air-vefl'els. But this hypothefis 
is inadinifflble on many accounts. 
The fenfible perfpiration of many plants is of a far dif¬ 
ferent nature from the above watery evaporation, and is 
to be confidered as an aftual fecretion. Such are the mu¬ 
cilaginous exudation found on the leaves of the Tilia eu- 
ropaea, or lime-tree ; the faccharine matter perceptible on 
orange-trees, hops, beech, and other plants, which is one 
kind of honey-dew, and either owing to fome injury to 
their roots, or to the fudden influence of a cold, or other- 
wife noxious, atmofphere. The Ciftus genus, and many 
other fhrubs of warm countries, afford a refinous exuda¬ 
tion from their leaves and young twigs. The Diftamnus 
albus, or fraxinella, is very remarkable for a highly im- 
flammable vapour, which in hot ffill weather ifl'ues from, 
and. hovers around, the plant, exploding on the approach 
of a lighted taper. Manna is faid to have been fcraped 
from the leaves of Fraxinus ornus, though ufually pro¬ 
cured only from the fap of that tree. A kind of wax 
may in like manner be obtained, as fome report, from the 
leaves of rofemary. A copious glutinous perfpiration is 
obfervable on young leaves of many kinds, as the cherry, 
plum, various poplars, and abundance of aromatic herbs. 
Pelargonium inquinans is Angular for its exudation of a 
foft oily matter, that ftains the fingers with a red or ver¬ 
milion-like tinge. 
PERSPI'RATIVE, adj. Performing the aft of perfpi¬ 
ration. 
PERSPI'R ATORY, arlj. Perfpirative.—The fineft ca¬ 
pillaries. and perfpii'alory duffs. Bp. Berkeley's Siris. 
To PERSPI'RE, v. n. [perfpiro, Lat.] To perforin ex¬ 
cretion by the cuticular pores. To be excreted by the 
fkin.—Water, milk, whey, taken without much exercife, 
fo as to make them perfpire, relax the belly. Arbatlinot. 
To PERSPI'RE, v. a. To emit by thepores.—Firs grow 
and thrive in the moff barren foil, and continually per¬ 
fpire a fine balfam of turpentine. Smollet. 
PERSTAI'N, a town of Bohemia, in the circle of Bo- 
leflaw : fourteen miles north-weft of Jung Buntzel. 
To PERSTRIN'GE, v. a. [peiftriiigo, Lat.] To touch 
upon ; to glance upon.—In thofe verfes of Callimachus 
he perjlringeth the impiety of Eumerus. Fotherby's Allieom . 
162a.—Men from this text of Scripture would perfiringe 
philofophy. More's Conj. Ca’ob. —The wotnanifhnefs of 
the church of Rome in this period is perjlringed. More 
011 the Seven Churches. 
Look out, look out, and fee, 
What objeft this may be, 
That doth perjlrihge mine eye. Burton's Anat. of Mel. 
PERSUA'DABLE, arlj. [from perfuade.'] Such as may 
be perfuaded. 
PERSUA'DABLY, adv. So as to be perfuaded. 
To PERSUA'DE, v. a. [ perfmdeo, Lat. perfuader, Fr.J 
To bring to any particular opinion.—Let every man be 
fully perfuaded in his own mind. Rom.x iv. 5.—We are 
perfuaded better things of you, and things that accom¬ 
pany falvation. Heb. vi. 9.—joy over them that ar e per- 
fuaderl to falvation. 2 Efdr. vii. 61.—Let a man be ever 
fo well perfuaded of the advantages of virtue, yet, till he 
hungers and thirds after righteoufnefs, his will not 
be determined to any aftion in purfuit of this confeffed 
great good. Locke. —Men fhould ferioufly perfuade them- 
lelves that they have here no abiding-place, but are only 
in their paffage to the heavenly Jerufalem. Wake's Prep, 
for Death. —To influence by argument or expoftulation. 
PerJ'uaJion feems rather applicable to the paflions, and ar¬ 
gument to the reafon ; but this is not always obferved. 
Johnfon. —Philoclea’s beauty not only perfuaded, but fo 
perfuaded as all hearts muff yield: Pamela’s beauty ufed 
violence, and fuch as no hearts could refift. Sidney. — 
They that were with Simon, being led with covetoufnefs, 
were perfuaded for money. 2 Mac. x. 20.—To fit crofs- 
legg’d, or with our fingers peftinated, is accounted bad, 
and friends will perfuade us from it. Brown. — I fhould 
be glad if I could perfuade him to write fuch another cri- 
tick on any thing of mine; for when he condemns any 
of my poems, he makes the world have a better opinion 
of them. Dryden. —To inculcate by argument or expof¬ 
tulation.—To children, afraid of vain images, we perfuade 
confidence by making them handle and look nearer fuch 
things. Bp. Taylor. —To treat by perfuafion. Not in uje. 
Twenty merchants have all perfuaded with him; 
But none can drive him from the envious plea 
Of forfeiture. Shakefpeare. 
PERSUA'DE, /. Perfuafion. Not in ufe. 
Indeed, Lucina, were her hufband from her. 
She happily might be won by thy perfuades. 
Soliman and Perfeda, 1599. 
PERSUA'DER, f. One who influences by perfuafion; 
an importunate advifer.—The earl, fpeaking in that im¬ 
perious language wherein the king had written, did not 
irritate the people, but made them conceive by the 
haughtinefs of delivery of the king’s errand that himfelf 
was the author or principal perfuader of that counfel. 
Bacon's Hen. VII. 
Hunger and third: at once. 
Powerful perfuaders! quicken’d at the feent 
Of that alluring fruit, urg’d me fo keen. Milton's P. L. 
PERSUASIBIL'ITY, f. Capability of being perfua¬ 
ded.—It is fufficient that the Gofpel fuggefts and offers 
fuch rational arguments and motives as are proper to be¬ 
get belief in moral agents; but the perfuafibility, or the 
aft of being perfuaded, is a work of men’s own. Ilally - 
well’s Saving of Souls, 1677. 
PERSUA'SIBLE, arlj. [ peifnafibilis, from perfuadeo, 
Lat.] To be influenced by perfuafion.—It makes us ap¬ 
prehend our own intereft in that obedience, makes us 
traftable and perfuajible, contrary to that brutifh ftub- 
bornnefs of the horfe and mule, which the Pfalmift re¬ 
proaches. Gov. of thcTongue. —Havingpower to influence. 
—My fpeech and my preaching, was not with enticing 
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