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/ to the Book itfelf; and that his Grandfon tranflated it into Greek, which likewife appears from the Prologue : that he made this Tranlktion in %ypt, where the Author lived in his ;S th Year ; that it was done under the Reign of Ptolomy Evergetes, Succeffor of Ptolemy Thiladelphus, who began to reign in the Tear of Rome 5"> 2 +° Years before Chrift ; that the Grandfather had intitled it •Parables, ' which the Grandfon changed into Ecclefiafticus, q. d. •Preacher : Laftly, that the Book, however, is attributed to the Tranflator, by Reafon he changed, and added many Things to the Original.

Fa. Calmet takes the Book of EcclefiaJliaiS to have been'compofed under the Pontificate of Ouias III. Son of Simon, and the Reign of Antiochus Epiphancs, King ot Syria. He adds, that neither the Author of the Latin Tranfiation, nor the Time when it was made, is known ; but being quoted regularly by all the Antient Fathers, there is no doubt of its being very Antient. He takes it to have been done by the Tranflator of the Book of Wifdom.

ECCOPE, Amputation, in Chirurgcry, a dividing of a fleiliy Part, and cutting off that which is gangreen'd, can- cer'd, or the like : As alfo an Amputation of an Excrefcence, f$c. See Amputation.

Eccope, is likewife ufed for a Kind of FracT:ure,_ or Solution of Continuity of the Skull, by a fimple Incifion. See Fracture.

The Word is fbrm'd from the Greek, IkkwIhp, to cut. ECCOPROTICKS, in Medicine, Laxative, or loofen'wg Remedies, which purge gently, by foftening the Humours and Excrements, and fitting them for Expulfion. See Evacuants, Purgatives, iSc.

The Word is compofed of the Greek Particle m, and rjir{&, Excrement.

ECHINATE Seeds, are fuch as are prickly and rough like the Coat of a Cheffnut ; or, as fome fay, like the Skin of a Hedge-hog. See Seed.

ECHINUS, in Architeflure, a Member, or Ornament, near the Bottom of the Ionic, Corinthian, and Compofite Capitals 5 which, from its circular Form or Contour, is called by the French, Qitart de Rond, and by the Euglifo, ghiarter round, or Soultin; and from its being uliiaily carved, or cut with Figures of Eggs, &c. is called alfo by the Latins, Ovum, by the Italians, Ovolo, the French, Ove, and the Evglifi, Eggs and Anchors. See Quarter- round and Ovolo.

Laftly, The Eggs being encompaffed with a Cover, and thus bearing fome Refcmblance to a Cheffnut cut open ; The Greeks have call'd it sjJV©-, Echinus, that is, Cheffnut. See Boultin, iS>c.

Echinus, among Botanifts, is ufed for the prickly Head, or Top of any Plant ; thus called from its Likenefs to an Hedge-hog or Cheffnut.

ECHIQUITE, in Heraldry. Sec Checky. ECHO, or ECCHO, a Sound refkaed, or reverberated, from a folid, concave Body, and fo repeated to the Ear. See Sound and Reflection.

The peripateticks, who took Sound for I know not what Species, or Image of the fonorous Body, impreffed on the adjoyning Air ; account for Echo from a Refilition of the Species, occafion'd by its meeting fome Obitacle in the Way. But the Moderns, who know Sound to confifl: in a certain Tremor, or Vibration, in the fonorous Body, com- municated to the contiguous Air, and by that Means to the Ear ; give a more confident Account of Echo.

For a tremulous Body, flriking on another folid Body, 'tis evident, may be repelled without deflroying or dimi- nifhing its Tremor ; and confequently a Sound may be re- doubled by the Refilition of the tremulous Body, or Air. See Sound.

But a fimple Reflexion of the fonorous Air, is not enough to folve the Echo : For then every plain Surface of a folid hard Body, as being fit to rcfleft a Voice or Sound, would redouble it ; which we find does not hold.

To produce an Echo, therefore, it fliould fcem_ that a Kind of Concameration, or Vaulting were neceffary, in order to colled, and by collecting, to heighten and increafe, and afterwards reflect the Sound ; as we find is the Cafe in reflecting the Rays of Light, where a concave Mirror is required.

In Effecl, as often as a Sound ftrikes perpendicularly on a Wall, behind which is any Thing of a Vault, or Arch, or even another Parallel Wall ; fo oft will it be reverberated in the fame Line, or other adjacent ones.

For an Echo to be heard, therefore, 'tis neceffary the Ear be in the Line of Reflexion : For the Perton who made the Sound to hear its Echo, 'tis neceffary he be perpendi- cular to the Place which reflefts it : And for a manifold or Tautological Echo, 'tis neceffary there be a Number of Walls and Vaults, or Cavities, either placed behind each other, or fronting each other.

A fingle Arch, or Concavity, Be. can fcarce ever flop and reflect all the Sound ; but if there be a convenient Difpofition behind it, Part of the Sound, propagated thither being collected and reflected, as before, will prefent another Echo : Or if thete be another Concavity, oppofed at a due Diftance to the former ; the Sound reflected from the one upon the other will be tofs'd back again by this latter c5c

Many of the Phenomena oi Echo's, are well confi'der'd by the Bifhop of Leighs, &c. Who remarks, that any Sound, falling either direfily, or obliquely, on any denfe Body, of a fmooth, whether plain or arched, Superficies is refkaed, or Echoes more or lefs. The Surface, fa\s'he, muft be fmooth, otherwife the Air, by Reverberation, will be put out of its Regular Motion ; and the Sound thereby broke and extinguished. He adds, that it Eccho's more or lefs, to (hew, that when all Things are, as before de- scribed, there is ftill an Echoing; tho' it be not always heard ; either becaufe the direft Sound is too weak to be beat quite back again to him that made it, or that it does return to him, but fo weak, that it cannot be difcern'd ; or that he fl-ands in a wrong Place to receive the refleaed Sound, which paffes over his Head, under his Feet, or on one Side ot him, and which therefore may be heard by a Man ftanding in the Place where the refleftcd Sound will come, provided no interpoled Body intercept it 5 but not by him that firft made it.

Echo's may be produced with different Circumftances : For,

1. A 'Plane Obftacle reflefts the Sound back in its due Tone and Loudnefs ; Allowance being made for the pro- portionable Decreafe of the Sound, according to its Diftance. See Plane.

2. A Convex Obftacle refleas the Sound fomewhat frnal- ler, and fomewhat quicker, tho' weaker, than it otherwife would be. See Convex.

5. A Concave Obftacle, echo's back the Sound, bigger, flower, and alfo inverted ; but never according to the Order of Words. Sec Concave.

Nor does it feem poffible to contrive any fingle Echo, that (hall invert the Sound, and repeat backwards : Be- caufe, in fuch Cafe, the Word laft fpoken, that is, which laft occurs to the Obftacle mufl be repell'd firft, which cannot be. For where in the mean Time fliould the firft Words hang and be conceafd ; or how, after fuch a Paufe, be revived, and animated again into Motion.

From the determinate Concavity, or Archednefs of the refleaing Bodies, it may happen that fome of them (hall only echo back one determinate Note, and only from one Place.

4.. The Echoing Body being removed farther off, it refleas more of the Sound than when nearer ; which is the Rea- fon why feme Echo's repeat but one Syllable, fome one Word, and feme many.

5. Echoing Bodies may be fo contrived, and placed, as that refleaing the Sound from one to the other, either di- rectly and mutually, or obliquely and by Succeffion, out of one Sound, (hall a multiple Echo, or many Echo's arife.

Add, that a multiple Echo may be made, by fo placing the Echoing Bodies, at unequal Distances, as that they may refka all one Way, and not one on the other ; by which Means, a manifold fucceffive Sound will be heard 5 one Clap of the Hands like many ; one Ha like a Laughter ; one fingle Word like many of the fame Tone and Accent ; and fo one Viol, like many of the fame Kind, imitating each other.

Laftly, Echoing Eodies may be fo order'd, that from any one Sound given, they ihall produce many Echo's, different both as to Tone and Intention. By which Means a Mufical Room may be fo contrived, that not only one Inflrument playing therein, (hall feem many of the fame Sort and Size, but even a Confort of different Ones ; only by placing certain Echoing Bodies fo, as that any Note play'd, (hall be return'd by them in 3 ds, 5 ths, and S ths.

Echo, is alfo u(ed for the Place where the Repetition of the Sound is produced, or heard.

The Word is form'd of the Greek, »x©"> Sonus, of the Verb «;$«, Souo, I found,

Echo's are diftinguiflied into divers Kinds, viz. 1. Single, which return the Voice but once 5 whereof fome are Tonical, which only return a Voice when modu- lated into fome particular Mufical Tone. Others, 'Poly- fyllabical, which return many Syllables, Words and Sentences. 1. Multiple, or Tautological, which return Syllables and Words the fame oftentimes repeated.

In Echo's, the Place where the Speaker (lands, is called the Centrum 'Phonicum ; and the Objca, or Place, that returns the Voice, the Centrum Phonocampticitm. See Centrum.

At the Sepulchre of Metella, Wife of Craffiis, was an Echo, which repeated what a Man (aid, five Times. Au- thors mention a Tower at Cyzicus, where the Echo re- peated feven Times.

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