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Balis, and then its vertex foremost, has or 125 feet in 1"; and the time of its
its reGftances, as the tangent to an arch passing through that space being about
of a circle, whose diameter is equal to ' or 'of ", the medium quantity of
the parameter, and the tangent equal to rehltance mult, in these instances, have
half the basis of the parabola. 5. The been about 120 times the weight of the
resistances of an hyperbola, or the semi- ball; which as the ball was nearly
ellipsis, when the base and when the t'a of a pound, amounts to about 10 it.
vertex goe foremost, may be thus com- avoirdupoise.
puted ; let it be, as the sum, or dif-

Now if a computation be made, accorda ference, of the transverse axis, and latus ing to the method laid down for comrectum, is to the transverse axis, so is

pressed Auids in the 38th Propos. of lib. the square of the latus rectum to the square 2. of Sir Isaac Newton's Principia, fupof the diameter of a certain circle ; in

posing the weight of water to be to the which circle apply a tangent equal to weight of air, as 850 to 1, it will be haif the basis of the hyperbola or ellipsis. found that the resistance of a globe of Then say again, as the sum, or differ- three quarters of an inch diameter, mov. ence, of the axis and parameter is to the ing with a velocity of about 3600 feet parameter, so is the aforesaid tangent to in 1", will not, on those principles, another right line. And further, as the

amount to any more than a force of sum, or difference, of the axis and pa.

4; 15. avoirdupoise; whence we may rameter is to the axis, so is the cir

conclude (as the rules in that proposition cular arch, corresponding to the afore- for flow motions are very accurate) that faid tangent, to another arch. This done, the regitances will be as the tangent to

the refifting power of the air in flow

motions is less than in swift' motions, in the fum, or difference, of the right line

the ratio of 4 to 10, a proportion bethus fouod, and that arch last mentioned.

tween that of 1 to 2, and I to 3.
6. In general, the resistances of any
figure whatsoever going now with its

Again charging the fame piece with base foremost, and then with its vertex,

equal quantities of powder, and balls of

the same weight, and firing three times are as the figures of the bafis to the fum of all the cubes of the element of the

at the pendulum, placed at 25 feet dis. bafis divided by the squares of the ele

tance from the mouth of the piece, the

medium of the velocities with which the ment of the curve line. All which rales, he thinks, may be of

ball impinged was 1690 feet in 1". use in the fabric or construction of ships,

Then removing the piece 175 feet from and in perfecting the art of navigation

the pendulum, the velocity of the ball,

at a medium of five shots, was 1300 universally. As also for determining the feet in ". Whence the ball, in passing figures of the balls of pendulums for

through 150 feet of air, loft a velocity of clocks. See the article Ship, &C. As to the resistance of the air, Mr.

about 390 feet in 1"; and the rebtance, Robins, in his new principles of gun.

computed from these numbers, comes

out something more than in the preceding nery, took the following method to de.

instance, amounting to between 11 and termine it : he charged a musket-barrel three times successively with a leaden

12 pounds avoirdupoise : whence, acball $ of an inch diameter, and took

cording to these experiments, the refiftsuch precaution in weighing of the pow

ing power of the air to swift motions is der, and placing it, as to be lure, by many

greater than in flow ones, in a ratio previous trials, that the velocity of the

which approaches nearer to the ratio ball could not differ by 20 feet in i" from

of 3 to i, than in the preceding expe

riments.
its medium quantity. He then fired it
against a pendulum, placed at 25, 75,

Having thus ascertained the resistance to and 125 feet distance, &c, from the

a velocity of near 1700 feet in i", he mouth of the piece respectively. In the

Dext proceeded to examine this resistance first cale it impunged against the pendu.

in smaller velocities : the pendulum be. lem with a velocity of 1670 feet in i";

ing placed at 25 feet distance, was fired in the second case with a velocity of

at five times, and the mean velocity with 1550 feet in 1"'; and in the third case

which the ball impinged was 1180 feet with a velocity of 1425 feet in z''; so

in 1". Then removing the pendulum to that in passing through so feet of air,

the distance of 250 feet, the medium vethe bullet loft a velocity of about 12.0,

locity of five shot at this distance, was 950 feet in a"; whence the ball, in pas,

hing

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sing through 225 feet of air, loft a ve- for what is more usually called analysis, locity of 230 feet in 1", and as it passed or the analytic method. See the articles through that interval in about of ", ANALYSIS and METHOD. the resistance to the middle velocity will RESOLUTION, in medicine, that coction come out to be near 331 times the gra

or alteration of the crude peccant vity of the ball, or 2 1b. 10 oz, avoir- matter of any disease, either by the dupoile. Now the resistance to the fame natural Arength of the patient, or of velocity, according to the laws observed its own accord, or by the application of in flower motions, amounts to 1 of the remedies, whereby its bulk, figure, cosame quantity; whence in a velocity of helion, &c. are lo far changed, as that 1065 feet in i", (the medium of 1180 it ceales to be morbid, and becomes and 950) the relifting power of the air is laudable. This Boerhaave observes, is augmented in no greater proportion than

of all others the most perfect cure, where of 11 to 7; whereas in greater degrees

it is effected without any evacuation, as of velocity, as before, it amounted very

supposing the matter favourable, the connear the ratio of 3 to 1.

ftitution excellent, and the medicines good. That this refifting power of the air to Resolution, in mufic, is when a canon swift motions, is very sensibly increased or perptual fugue is not wrote on a line, beyond what Sir Isaac's theory for flow or in one part, but all the voices that mations makes it, seems hence to be are to follow the guide or firit voice ale evident. It being, as has heen said, in wrote separately either in score, that is in musket, or cannon fhot, with their full separate lines, or in separate parts, with charge of powder, near three times the the pauses each is to oblerve, and in the quantity assigned by that theory.

proper tone to each. The resítance of a bullet of three quar.

RESOLVENTS, resolventia, in medicine, ters of an inch diameter, moving in air remedies proper to resolve and dissipate with a velocity of 1670 feet in 1", tuntors and gatherings, to soften induamounting, as we faid, to 10 lb, the rations, and, by their tenuity and warmth, resistance of a cannon ball of 24 lb. fired evacuate redundant and peccant humours with its full charge of powder, and

through the pores. Under this class thereby moving with a velocity of 1650 come various unguents, emplasiers, &c. feet in i", may hence be determined. RESONANCE, RESOUNDING, in mulir, For the velocity of the cannon ball be- &c. a sound returned by the air, inclofed ing near the same as the musket bullet, in the bodies of Atringed musical instru., and its surface above 54 times greater,

ments, as lutes, &c. or even in the it follows, that the resistance on the can- bodies of wind inftruments, as flutes, &c. pon ball will amount to more than 540 lb.

See SOUND and MUSIC. which is near 23 times its own weight. Elliptic and parabolic vaults, resound And from hence it appears how rach and Itrongly, that is, they will reflect or reerroneous the opinion of thole is, who

turn a sound. The mouth and the parts neglect the confideration of the resistance thereof, as the palate, tongue, teeth, of the air as of no importance in the

nose, and lips, Monsieur Dodart observes, do&trine of proje&tiles. See the articles

contribute nothing to the tone of the PROJECTILES and GUNNERY.

voice, but their effect is very great as to RESISTANCE of the fibres of solid bodies

the resonance: of this we have a very is more properly called cohesion. See sensible instance in that vulgar inftru. the article COHESION.

ment called a jews-harp, or trompe

de Solid of leaft ResisTANCE. See SOLID. Bearn; for if you hold it in your hand, RESOLUTION, in chemistry, &c. the and strike the tongue or spring thereof, reduction of a mixed body into its com

which is the method practifed to found ponent parts, or first principles, by a this instrument, it yields scarce ary proper analysis. See the articles MEN. noise, but holding the body of it between STRUUM and SOLUTION.

the teeth, and striking it as before, it The resolution of bodies is effe&ted by makes a musical buzz, which is heard divers operations, as distillation, subli. at a good distance, and especially the mation, fermentation, precipitation, &c. lower notes. See the articles DISTILLATION, SUB

So also in the haut-boys, the tune of the LIMATION, &C.

reed is always the same ; being a sort of Some logicians use the term resolution drone, the chief variety whereof is in VOL. IV.

the

26 с

the tune of resonance produced in the ed by the diaphragm, which is so conmouth, by the greater or less åperture, nected with the ribs and vertebræ, that

and the various motions of the lips. the air cannot enter the thorax in such RESORT, or Ressort. See RESSORT, a manner as would be requisite for an RESPECTU COMPUTI VICECOMITIS equilibrium. See the article LUNGS,

HABENDO, in law, a writ directed to DIAPHRAGM, & c. the treasurer and barons of the ex- Since, therefore, in inspiration, a greater chequer for the respiting of a theriff's quantity of air enters the lungs through acrount.

the glottis, it will extend the lungs RESPIRATION, respiratio, the act of more, and overcome their natural force,

refpiring, or breathing the air. What so that in this action the lungs are respiration is, and why it is uninter- passive; but how far they are active is ruptedly carried on without the concur- only to be discovered from certain pharence of the mind, will appear from the nomena, In vital inspiration, then, following confiderations of Boerhaave. especially considered in a sleeping perThe lungs fufpended in the air, which fon, first the ribs, particularly the nine every where acts upon them, and equally superior ones, articulated at the vertebræ, presses them always, collapse, contract and by cartilages joined to the fternum, themselves into a smaller space, and be- with their arched part, rise to the clacome much less than when they remain- vicles, so that this motion is principally ed in the intire thorax. This is prin- observed in the middle of the arch, cipally performed by the contractile force whilst three, or perhaps four, inferior of the muscular fibres, which connect ribs are turned downwards, backwards, the squamous segments of the bronchia. and obliquely outwards, but in such a If the lungs thus contracted, are filled manner that the seventh, eighth, ninth, with air, forcibly blown through the and tenth ribs are by their cartilaginous glottis, they are lo diltended as in bulk segments, as it were, drawn inwards. not only to equal that which they had Secondly, the whole abdomen, to the in the intire thorax, but even to exceed very end of inspiration, is gradually it; all which is fufficiently certain from rendered more tumid and pressed downexperiments. The saine thing happens wards. Thirdly, at the same time the if, when an access for the air through cavity of the thorax is enlarged, as is the glortis is left to the lungs, the air, obvious from repeated experiments. externally acting on the langs, is either Whilft the parts remain in this fituation, removed, or its pressure diminished. the air acts upon the lungs with a force Hence it is obvious, that the lungs, by equal to that with which the thorax retheir proper force have always a ten- fifts, in that the lungs will remain in a dency to become less in all their parts state of reft. Hence less blood will pass than they are when placed in the intire through them, and a smaller quantity thorax. For this reason, it is certain of it will be forced into the left ventricle that they are in a continual state of di- of the heart, and consequently less blood ftraction so long as a person is alive, lo will be conveyed to the cerebellum and that they must collapse, and be dimi. its nerves. The arterial blood will also nished, whilst the whole of the animal act less upon the intercoltal muscles and remains in a vacuum, obtained by an diaphragm, so that the causes dilating exhaustion of the air in an air-pump. the thorax are weakened. Hence the For there is nothing similar to a cir. elasticity of the cartilaginous fegments cumambient air between the external again depresses the ribs, in which work membrane of the lungs, and all the in- they are also assisted by the muscular ternal surface of the pleura in a sound fibres arising from the ide of the person; nothing therefore externally fternum within the thorax, and inserted compresses the lungs, except the di. into the bony extremities, and cartilages aphragm. There is, however, always of the true ribs. At the same time the an internal air contained in them, and diftraéted fibres of the peritonæum and freely conveyed to them through the abdominal muscles restore themselves. glottis. Hence the lungs are always Herce the compressed viscera thrust the somewhat more diftended by the injernal, relaxed diaphragm upwards into the than they are compreited by the exa thorax, which is by this means conternal, air, the access of which is hinder, tracted, and the air expelled from the

lungs,

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lungs. By this means, expiration and but carries farther, making it the true
the action already mentioned, are per- cause of the diaftcle of the heart, which
formed. But in a particular manner by neither. Borelli, Dr. Lower, nor Mr.
these two actions the blood is not only Cowper, had well accounted for. See
carried through the lungs, but its motion the articles DIASTOLE and SYSTOLE.
accelerated. See CIRCULATION, &c. From experiments made upon dogs, and
Phyficians are not agreed about the use other animals, Dr. IIales Mews, that
and effects of refpiration; some think without respiration, the blood would
that the air is intinuated into the veilels foon turn putrid and pestilential; ani
of the lungs, to give a greater fluidity indeed the only animal exempied from
and motion to the blood; others, that the necality of iepirsticn is a foetus.
it conveys yıry fubiile nitrous rorpuscles Sve the article Tourt's.
thereunto, which gives it the red colour; With regard to the face of refpiration,
others again believe the air leves 10 the lait mentidad a lithor ohieve, that
condenle the blood, which has been though a man by a peculiis adion of his
heated by circulation. This is certain, mouth and tongue, niny luck mercury
that the air entering into the lungs, and twerty-two inches, and iome ined twienia
all the finall ramifications which lur- ly loven or ticity tight, hish, yet he
round its vehicles is broke, com:nior:ted, found from experience, that by the bare
and rendered more fluid, and that it is inipicing action of the diaplir gm and di-
deprived of a ferofity, which proceeds lating thorax, he himself could scarcely
from the lungs by perfpiration in the raile the mercury iwo inches, at which
form of a vapour that is viñible in cold time the diaphragm must act with a force
weather. It may be added, that the equal to the weight of a cylinder of mer-
voice, laughter, coughing, fneezing, cury, whole baie is commensurate to the
yawning, and sucking, depend upon fe- area of the diaphragm, and its beight two
spiration. Boerhaave takes the principal inches, whereby the diaphragm muft at
ules of respiration to be the further pre- the same time luft in a weight equal to
paration of the chyle, its more accurate many pounds; neither are its counteract-
mixture with the blood, and its conver- ing muscles, those of the abdomen, able
fion into a nutritious juice, proper to to exert a greater force.
repair the decays of the body, Oiher With regard to the quantity of moisture
authors take a great use of respiration carried off by respiration, the Doctor,
to be, by the neighbourhood of the cold from an experiment on wood-athes,
nitrous air, to cool the blood coming estimates that quantity to be equal to
reeking hot out of the right ventricle of seventeen grains in fifty expirations,
the heart through the lungs, and to act whence there will proportionably be four
as a refrigeratory; others affert one hundred and eight grains evaporated or
grand use ot respiration to be the throw- breathed off in twelve hundred expira-
ing off the fuliginous vapours of the tions, being the number in an hour, and
blood, along with the expelled air; and thence in twenty four hours 9792 grains,
for inspiration they asert, that it conveys or 1.39 pounds, which suppoting the fur-
a nirro-aerial ferment to the blood, to face of the lungs to be 41635 square
which the animal spirits, and all muro inches, then the quantiry evaporated from
cular motion, are owing. But Dr. that inward surface will be
Thurston reje&s all these, as being the of an inch depth.
principal uses of respiration, and from From the violent and fatal effects of very
the experiments of Dr. Croon, Dr. Hook, noxious vapours on the respiration and
and others, made before the Royal So. life of animals, the Doctor thews how
ciety, he thews the principal use of re- the respiration is proportionably incom-
{piration to be that of moving, or pale moded when the air is loaded with letter
fing the blood from the right to the left degrees of vapours, which vapours do in
ventricle of the heart, and so 1o effect some measure clog and lower the air's
circulation; whence it is, that persons elasticity, which it bet regains by bavo
hanged, drowned, or ftrangled, fo fud. ing these vapours dispeiled by the venti-
denly die, viz, because the circulation tilating motion of ine tice open air, that
of the blood is stopped, and for the is belt rendered whollome by the agita-
same reason it is, that animals die fo ~ tion of winds; thus what we call a close
speedily in the air-pump. This use of warm air, such as has been long contined
respirativa Dr. Drake no: ori, scofirms, in a room, without leaving the vapouss

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in it carried off by communicating with RESPONSE, an answer or reply. A word the open air, is apt to give us more or chiefly used in speaking of the answers less unezfinels in proportion to the quan. made by the people to the priest, in the lity of vapours which are floating in it. litany, the psalms, &c. And thus many of those who have weak RESSAULT, in architecture, is the effect lungs, but can breathe very well in the of a body which either projects or finks fresh country air, are greatly incommod- back ; that is, ftands more out or in, ei in their breathing, when they come than another, so as to be out of the line into large cities where the air is full or level with it. of fuligenous vapours; and even the RESSORT, or Resort, a french word, most robust and healthy, in changing sometimes used by english authors, to fig. from a city to a country air, find an ex- nify the jurisdiction of a court, and parhilerating pleasure arising from a more ticularly one from which there is no apfree and kindly inspiration, whereby the peal. lungs being less loaded with condensing Thus it is said, that the house of lords aii and vapours, and thereby the vesicles judge en dernier reffort, or in the last res. more dilated with a clearer and more fort. elaltic air, a freer course is thereby given RESSOURCE, a french word, used by enge to the blood, and probably a purer air Jish writers, to denote an after-game, for

mixed with it. See the article AIR. recovering a person's losses, or something KESPITE, in law, &c. fignifies a delay, to appiy hack for succour,

ford arance, or prolongation of time, REST, quies, the continuance of a body in granted any one, for the payment of a the same place, or its continual applicadelt, or the like.

tion or contiguity to the same parts of RESPONDENT SUPERIOR, in law, is a the ambient or contiguous bodies; and,

superior's answering for the insufficiency therefore, is opposed to motion. See the of an inferior. Thus, if the theriffs of article Motion. London are insufficient, the lord-mayor Sir Isaac Newton defines true or absolute and commonalty must answer for them, rest, to be the continuance of a body in as the sheriffs superior.

the same part of absolute space; and reSuperior officers must also answer for their Jative rest to be the continuance of a bo. deputies, in civil actions, in case they are dy in the same part of relative space. See infuflicient to answer damages; as where the article SPACE. a gaoler deputes another under him, and It is one of the laws of nature, that matthe perfon deputed suffers an escape, the ter is indifferent to motion or rest, as bas gaoler mult answer for his deputy's in- been Mewn under the article INERTIA. fufficiency.

Reft, confidered in a physical view, is RESPONDENT, in the schools, one who only falutary, in so far as it is duly pro

maintains a thesis, in any art or science ; portioned to the exercise; for a sedentary who is thus called, from bis being to an. idle life brings on many indispositions. swer all the objections proposed by the See the article EXERCISE. opponent.

Rest, in poetry, is a short pause of the The relpondent is to see whether the voice, in reading, being the same with pohtion inade by the contrary party be the cæsura, which, in alexandrian verses, jutt and legitimate ; or whether some of falls on the sixth lyllable ; but in verses the laws of opposition be not brcken.

or eleven fyllables, on the He is also to manage the modes and fourth. See the articles CÆSURA, figures of the syllogilms, to fee wherher ALEXANDRIAN, &c. the premises be juít; and through the REST, in music, the same with pause. See whole, to answer rather by diftinguos, the article PAUSE. than by dire&t negation. ,

RESTAURATION, the act of re-esta. RESPONDENT, in law, a person who un. blissing or fetiling a thing in its former dertakes to answer for another; and allo,

good itate. one who binds himself as a fecurity for RESTAURATION, in architecture, the act ang her person's good behaviour,

of repairing those parts of a building RESPONSALIS, in law, is a person who that are gone to decay, in such a manan vers for another, in court, at a day her as to give it its original ftrength and inned.

beauty, KISPONSARY SONG, an anthem, in From the plinths of the corinthian cee which the chacuilters fing by turns.

lumns vi the Pantheon, which are almoft

wholly

of ten

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