Page:Cyclopaedia, Chambers - Volume 1.djvu/999

 HEX

taken any Number of Times, never equals or Exceeds the other. See Quantity.

Heterogeneous Surds, are fuch as have different raoical Signs, as, ■/* a a, and y" : b b : /' 9, and V 19-

How to reduce Heterogeneous Surds to Homogeneous ones; Tee under the Article Surds.

HETERORHYTHMUS, a Term ufed by foine fan- ciful Writers, for a Courfe of Life unfuitable to the Age of thofe who live it.

The fame is alfo applied to Pulfcs, when they beat varioufly or irregularly in Difeafes. See Pulse.

The Word is compounded of the Greek, S7if9-, and fuS/tit. See Rhyme.

HETEROSCI1, in Geography, a Term vulgarly ap- plied to thofe Inhabitants of the Earth, whofe Shadow, at Noon-tide is always projected the fame Way. See Shadow. In this Senfe, the Inhabitants of the temperate Zones ate denominated Heterofcii. See Zone.

Heteroscii, however, in Strictnefs, and according to the Origin and Reafon of the Word, is a Term of Rela- tion 5 and denotes thofe Inhabitants, which, during the whole Year, have their Noon-tide Shadows projected dif- ferent Ways from each other.

Thus, we who inhabit the Northern temperate Zone, are Heterofcii with Regard to thofe who inhabit the Southern temperate Zone : And thofe are Heterofcii with Refpect to us.

Prom this Definition it follows, that only the Inhabi- tants of the two temperate Zones are Heterofcii ; nor is the Word ordinarily applied to any other. Tho', in Rea- lity, there is always one Part of the torrid Zone, whofe Inhabitants are Heterofcii with Regard to thofe of the reft, and with Regard to thofe of one of the temperate Zones, except at the Time of the Solftices. And even at that Time all of the torrid Zone are Heterofcii with Regard to thofe of one of the temperate Zones.

But as this is variable, and the People of the torrid Zone have their Shadow now on this, and then on that Side ; the Cuftom is to call them Amphifcii, and not Heterofcii. See Amphiscii.

The Word is Greek, form'd of 'in;©-, other, different ; and aula,, Shadow.

HETEROUSII, Heterousians, a Sect, or Branch of Arians ; the Followers of Aetius, and from him alfo de- nominated Aetians. See Aetians.

They were called Heteroufiani, by Reafon they held, not that the Son of God was of a Subftance like, fimil-ir to that of the Father ; which was the Doctrine of another Branch o{ Arians, thence-caled Homooufians, Homooujii : But that he was of another Subftance different from that of the Father. See Arian and Homoousian.

The Word is Greek, compofed of srs{©-, alter, and im*, Subftance.

HEXACHORD, in the antient Mufic, a Concord commonly called by the Moderns, a Sixth. See Concord and Sixth.

. The Hexachord is two-fold, Greater and Lejfer. —. The Greater Hexachord, is compofed of two greater Tones, two leffer Tones, and one greater Semitone ; which make five Intervals. The Leffer Hexachord confifis only of two greater Tones, one leffer Tone, and two greater Semitones. See Tone.

The Proportion of the former, in Numbers, is as 3 to 5 ; and that of the other, as 5 to 8.

The Word is Greek, compounded of e£, Sex, Six ; and ycf-fti, Corda, Chord, or String.

HEXAEDRON, or Hexahedron, in Geometry, one of the five regular Bodies, popularly call'd a Cube. See Cube and Regular Body.

The Square of the Side of a Hexaedron, is in a iub- triple Ratio to the Square of the Diameter of the cir- cumfcribed Sphere. — Hence, the Side of the Hexaedron is to the Side of the Sphere it is inferibed in, as 1 to the ■J 3 ; and confequently incommenfurable thereto.

The Word is Greek, form'd of 11, Sex, Six ; and U&> Sedes, Seat.

HEXAGON, in Geometry, a Figure of fix Sides, and as many Angles. See Figure and Polygon.

If thefe Sides and Angles be equal, it is called a Regular Hexagon. See Regular.

The Side of a Hexagon is demonftrated to be equal to the Radius of a Circle circumfcribed about the fame. See Circle and Radius.

Hence, a regular Hexagon is inferibed in a Circle, by fetting the Radius off fix Times upon the Periphery. See Inscribed.

To defcribe a Hexagon on a given Line A B, {Tab. Geometry, tig. 84.) draw an Equilateral Triangle A C B ;

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HEX

the Vertex C will be the Centre of a Circle, which will circumfcnbe the Hexagon required. See Circumscribing.

In Fortification, a Hexagon is a Fortrefs with fix Baftions. See Bastion.

The Word is Greek, form'd of %%, Sex, Six, and ■m/utl Augtdus, Angle. ' '

HEXAMERON, a Name given to divers Writings both of antient and modern Authors, containing Commentaries or Difcourfes, on the firft Chapter of Genefis- wherein is delivered the Hiftory of the Creation, or the firft fix Davs of the World. y

St. Bafil, St. Ambrofe, &c. have wrote Hexamerons.

The Word is Greek, V^&wyv, compofed of s|, Sex, Six and i>fi9ejt, which in the Doric Dialect is wrote ct/A^t, Day.

HEXAMETER, in the antient Poetry, a Verfe ufed by Greek and Latin Writers, confifting of fix Feet. See Foot and Verse.

The firft four Feet of a Hexameter, may be indiffe- rently either 2)atJyls or Spondees ; but the laft Foot, in Strictnefs, is always to be a Spondee ; and the laft but one a Dactyl. Such is that of Homer,

And that of Virgil,

Difcite Juftitiam moniti SS nori temnere T>hos.

Hexameter Verfe are di vided into Heroic ; which are to be grave and majeftical, fuitable to the Dignity of Heroic Poetry : And Satyrical, which may fee more loofe and negligent, as thofe of Horace. Sec Heroic, &c.

Epic Poems, as the Iliad, Odyffee, JEneid, &c. confift of Hexameter Verfes alone : Elegies and Epiftles ordinarily confift alternately of Hexameters and Pentameters. See Pentameter.

Some of the French and Engliflo Poets have attempted to compofc in Hexameter Verfes, but without Succefs. Jodelle made the firft Effay in 1553, with a Diftich in Praife of Olivier de Magny, which Pafquier renrcfents as a Mafter-picce. 'Tis this,

"Phoebus, Amour, Cypris, veut Sauver, nourrir £2 orner "ton Vers, S? ton Chef, d'CJmbre, de Flamme, de Fleurs.

But this Kind of Poetry plcafes no Body. The Modern Languages are not at all fit for a Kind of Verfe whofe Cadence depends altogether on long and fhort Syllables. See Quantity, Verse, ££c.

The Word is Greek, compofed of t*, Six, and (itt&fi Menfura, Meafure, Foot.

HEXAMILION, Examillion, in Antiquity, a cele- brated Wall built by the Emperor Emanuel, over the Ifthmus of Corinth.

It took its Name from & Six, and fuwor, which in the vulgar Greek fignifies a Mile ; as being fix Miles lone.

The Defign of the Hexamiliou, was to defend Pelo- ftonnefits from the Incurfions of the "Barbarians. — Amu- rath II. having rais'tl the Siege of Conflantinople, in the Year 1424 ; demolifti'd the Hexamiliou, tho' he had before concluded a Peace with the Greek Emperor.

The Venetians reftor'd it in the Year 14(13, by thirty Thouland Workmen, employ'd for fifteen Days, and co- ver'd by an Army commanded by Bartholdo d'E/le General of the Land Forces, and Louis Loredano Ge- neral of the Sea.

The Infidels made fcvcral Attempts upon it, but were repulfed, and obliged to retire from the Neighbourhood thereof. But Bartholdo being kill'd at the Siege of Corinth, which was attempted foon after ; 'Bertiuo Calcinate, who took on him the Command of the Army abandon'd, upon the Approach of the Beglerbeg, both the Siege and the Defence of the Wall, which had colt them fo dear : Upon which it was finally demolim'd.

HEXAPLA, or Exapla, in Church Hittory, a Bible dif- pofed in fix Columns, containing the Text, and divers Ver- fions thereof; compiled and publiihed by Origen. SecBiBLE.

Eufebius, ///jr. Eccl. L. VI. C. 16. relates that Origen, after his Return from Rome under Caracalla, applied himfelf to learn Hebrew ; and began to collect the ieveral Vcrfions that had been made of the facrcd Writings, and of thefe to compofe his Tetrapla and Hexapla : Others, however, will not allow him to have begun till the Time of Alexander, after he had retired into Palefiine, about the Year 231.

To conceive what this Hexapla was, it muft be ob- ferv'd, ' that bcfide the Tranflation of the facrcd Writings, call'd the Sepuagint, made under 'Ptolomy Philadelphia, above 270 Years before draft; the Scripture had been fince tranflated into Greek by other Interpreters. The firft of thofe Vsrfions, (or, reckoning the Septuagint, the fecondj was that oiAquila, about the Year of Chritt 140 : The third was that of Syramachus, publiflicd, as is commonly

fuppufed,