Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/604

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wrift than in the other, the blood ufually flows in the greateft violence from that fide of the nofe, or that noftril which is on the fame fide with the hand in the artery of which the re- bounding lias been moil violent. D1CTORES, in our old writers, is ufed for an arbitrator.

Blount. DICTUM, in our old writers, is ufed for an arbitrament or

award. Blount, in Diflores. Dictum de Kengkeortb, an edict or award between king Henry the Hid, and thole barons who had been in arms againfl him. It was fo called becaufe made at Kenel worth caftle in War- wickfhire, anno 51. Hen. 3. It contained a compofition of five years rent for the Lands of thofe who had forfeited them in that rebellion. Id. ibid. DI DAPPER, a common Englifh name for the fmall fpecies of colymbus or diver, very common in our rivers, and more commonly called the Dob-chick. See Dob-chick. DIDAR, among the Arabian authors, the name of the elm.

Ger. Emac. Ind. 2. DIDELPHIS, the name by which Linnseus calls the animal called philander by other writers. This creature, in that au- thor's fyftem of zoology, is alfo a diftindt genus of animals, the character of which is their having eight paps placed be- tween the duplicature of the abdomen. Linnxi fyftema natu- rae, p. 36. DIDYNAMIA, in botany, a clafs of plants, whofe flowers have two of their male parts or ftamina of greater efficacy in the action of impregnation of the feeds than the others : they are known by the two efficacious ftamina being always much longer than the others.

The word is formed of the Greek A/?, twice, and Awaits, power or efficacy. Of this clafs of plants are thyme, laven- der, bafil, &c.

This clafs comprehends the plants called by Rivinus monope- tall irregidares y or plants with flowers of an irregular fliape, but formed of one leaf; and the plants with labiated or perfonated flowers, according to Tournefort. There are cer- tain general characters which are found in all of this clafs. The perianthium is one leaved, erect, and tubular ; it is divi- ded at the end into five fegments, which are ufually unequal in fizc, and it remains after the flower is fallen. The flower confifts of one petal, and ffands erect : itsbafe always contains honey, and ferves in the place of the nectaria of other flowers. The verge or limb of the flower is ufually ringent or gaping, the upper lip is ftrait, and the under one broader than the up- per, and divided into three fegments, of which the middle one is the largeft. The ftamina are four filaments of a fubu- lated fhape ; they are fixed to the tube of the flower, and placed near its back. Two of thefe are ufually lon- ger than the other four. Thefe ftand near one another, and are placed in the middle : they are all placed in a parallel direction, and rarely exceed the length of the flower. The antherae are ufually laid under the upper Up of the flowers, and are placed in pairs, joining together near their tops. The germen of the pi Mil ufually ffands above the receptacle or cup ; the ftyle is fingle and capillary, and is bent in the fame directi- on with the ftamina ; it ufually ftands among them, and a little exceeds them in length ; its top alfo is a little crooked, and the ftigma is commonly emarginated. Many of the ge- nera of this clafs have no fruit, but the feeds are contained naked in the cup ; and when there is a fruit, it ufually con- tains two cells. When there is no feed-veffel, the feeds are contained in the bottom of the cup, and are four in number j and in focfa plants as have a feed-veffel, they are ufually more than four, and are always affixed to a fort of placenta within the capfule.

The flowers of the far greater part of thefe plants ftand erect, or nearly fo, making only a fmall angle with the ftalk ; by this means the antherae are much better defended from Injuries than they otherwife would be ; and, by means of this pofition, the farina, when difcharged from the antherze, na- turally falls upon the ftigma of the piftil, and is in little danger of being loft. The characters of this clafs of plants are de- livered as general, not particular: moft of them are found regularly in all the plants of it, but fome vary in one or other of the particulars, and to this is owing the diftinction of the feveral genera. This is a remarkably natural clafs of plants, not one fpecies of it deviating from the characters of the reft; though there are fome of thofe plants which have only two ftamina, which feem otherwife entitled to a place in it. Such are the pinguicula gratiola, verbena lycopus, and the like. Thefe however cannot be received into it, becaufe the effential character of it is that the ftamina are four in number, two longer and two fhorter. Lirmai Gen. Plant. p. 261.

Linnseus divides this clafs of plants into two general feries. The firft the gymnofpermia, and the fecond the angiofpermia. The firft of thefe comprehends the labiated plants of Tourne- fort, and the verticillate plant of Mr. Ray's method, and the other the perfonated plants of Tournefort. The gymnofpermia, or verticellate plants, are diftinguifhed from the reft, by having the feeds four in number, and ftarid-

ing naked in the cup ; and the ftigma divided into two fedgments, the lower of which is crooked. The angiofpermia, or perfonated plants, are diftinguifhed from the others, by always having a feed veftel of fome form though very various j and, by the ftigma being obtufc and various.

Of the firft kind, or gymnofpermia, are the galeopfis and ballota, with the like; and, of the fecond kind, or angio- fpermia, are the antirrhinum, &c. DIEBEL, in ichthyology, a name given by Kentman and others to the chubb or capito. It is properly a fpecies of the cyprinus. See Capito and Cyprinus. DIELCYSTINDA, among the antients, a kind of exercife per- formed by boys, who being divided into two parties or fides, each endeavoured to draw the other over to their fide, and the party which prevailed gained the victory. Hofm. Lex. in voc. DIEMERES, in the antient mufic, a word ufed fometimes alone, and fometimes joined with the word phorbeia. It ex- preffed a fort of bandage, ufed by the antients, to tie up the lower lip in playing on the pipe. The other kind of phorbeia confifted only of one perpendicular piece, which went down the cheek, and one tranfverfe one which covered the whole mouth, but had a hole cut into it, to admit the mouth-piece of the pipe. See Phorbeia. DIESIS (Cycl.) — Ariftoxenus, and other antient muficians, often mention the tone as divided into four parts, and the femi- tone into two j thereby making ten divifions or diefes in the fourth. And this is true, if we confider thefe founds in one tenfion ; that is either afcending or defcending: but accu- rately fpeaking, when we confider all the diefes or divifions of a fourth, both afcending and defcending we fhall find thir- teen ; five to each tone, and three to the femi-tone major. But then it is to be obferved, that fome of thefe divifions will be lefs than the enharmonic Diefis : for, if we divide the femi- tone major, into the femi-tone minor, and enharmonic Die_/is t afcending; for inftance, E, hi E, F, and then divide in hke manner defcending F, b F, E, we fhall have the femi-tone major divided into three parts : thus, E, b F, t\ E, F ; where the interval between b F and tj E, is lefs than the enharmonic Diefis between E & b F, or between fcj E & F. Phil. Tranf. N° 481. p. 273.

But if we fuppofe thefe fmall intervals equal, by increafing the leaft divifion, and diminifhing the true enharmonic Diefis y we fhall then have a fourth divided into thirteen equal parts ; and this naturally leads us to divide the octave into thirty-one equal parts, which gives us the celebrated temperament of Huygens. See Temperament.

The logarithm or meafure of the octave * being 1. 000,000, the meafure of the Diefis 44? will be o. 034215. Hence 29 Diefes will be nearly equal to the octave. Eider. Tentam. Nov. Theor. Mufc. p. 106. See Interval. DIEXAHAEDRIA, in natural hiftory, the name of a genus of fpars. The word is derived from the Greek J^s, twice e£ fix and t£& fide. The bodies of this genus are fpars, com- pofed of twice fix planes, being formed of two hexredral pyra- mids, joined bafe to bafe, without any intermediate column. Of this genus there are only two known fpecies. 1. One with long, narrow, and fharp pointed pyramids, found in lamb's cave on mendip hills : and 2. one with long, broad, and obtufe pyramids: this is found in the mine of Goffelar in Saxony, and in many of the mines of the hart's foreft. JiiU's hift. of Foffils, p. 213. DIEXODUS, ArtJJeJ©-, in rhetoric, is ufed for digreffion. DIFFARREATION, Diffarreaiio, in antiquity, a religious cere- mony, ufed upon occahon of obtaining a divorce. It was di- rectly oppofed to the ceremony of contracting marriage, called Confarreation. Pitifc. Lex. Ant. in voc. See Confak- reation, Cycl. DIFFERENCE (Cycl.) — It was a fundamental principle among the antient geometers that the difference of any two unequal quantities, by which the greater exceeds the leffer, may be added to itfelf, till it fhall exceed any propofed finite quantity of the fame kind. This principle feems incon- fiftent with the fuppofition of an infinitely fmall quantity or difference, which added to itfelf any number of times, is ne- ver to be fuppofed to become equal to any finite quantity what- foever ; which is the foundation of the modern method of infinitefimals. However, this laft may, with proper caution, be made ufeful and accurate. Vid. Madaurhh fluxions Introd. p. 4. and art. 495. feq. DIGASTRICUS {Cycl) — The Digaftric mufcle, accord- ing to Winflow, is a fmall long mufcle fituated laterally between the whole bafis of the jaw and the throat. It is flefhy at both the extremities and tendinous in the middle, as if it confifted of two fmall mufcles joined endwife by a tendon. It is fixed by one flefhy extremity in the fulcus of the maftoide apophyfis, and from thence runs forward inclining to the os hyoides, where the firft flefhy body ends in a round tendon, which is connected to the lateral part and root of the cornua of that bone by a kind of aponeurotic ligament, and not by a pulley, as appears at firft fight, becaufe of its paf- fage by the extremity of the mufculus ftylogloffus. Here

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