T 11 I 



Yhus liaving in the right-angled triangle CAD, the hypothe- 

 nufe A C, and the fide A D, the angle A is found thence. 

 After the fame manner is B found in the other C D B, from 

 C B and D B given. 



12. Given the three angles A, B, and C, to find any of 

 the fides. Since in lieu of the given triangle, another may be 

 afliimed, whofe fides are equal to the given angles, and the 

 angles to the given fides : this problem is refolved after the 

 fame manner as the preceding one. 



TRIGONUM, or Triarigiilar Harp, an ancient mufical 

 inftrument. ( See Plate of ancient Injlruments. ) One of this 

 Icind was taken from an ancient painting in the mufeum of 

 the king of Naples, in which it is placed on the fhoulder of 

 a little dancing Cupid, who fupports the inftrument with his 

 left hand, and plays upon it with his right. The trigonum 

 is mentioned by Athenajus, lib. iv. and by Julius Pollux, 

 lib. iv. cap. 9. According to Athenoeus, Sophocles calls it 

 a Phrygian inftrument ; and one of his Deipnofophifts tells 

 tis, that a certain mufician of the name of Alexander Alex- 

 andrinus was fo admirable a performer upon it, and h-ud 

 given fuch proofs of his abilities at Rome, that he made 

 the inhabitants fxao-oj^aviiv, mufically mad. It may not be un- 

 worthy of remark, that this little inftrument refembles the 

 Theban harp, in the circuniftance of wanting one fide to 

 complete the triangle. The performer too, being a native 

 of Alexandria, as his name implies, makes it probable it 

 was an Egyptian inftrument upon which he gained his repu- 

 tation at Rome. 



TRIGUERA, in Botany, was fo called by the late abbe 

 Cavanilles, in honour of his friend Don Candido Maria de 

 Trigueros, who gathered this plant, then fuppofed entirely 

 nondefcript, in Andalufia. Another genus was originally 

 thus defignated, now Lagunaa lobata of Willdenow, Sp. 

 PI. v. 3. 733. The prefent feems to be a good genus, 

 though the plant on which it is founded proves to be the 

 rare and little-known Verbafctim OJbectii of Linmus, as the 

 writer of the prefent article firft dii'covered. — Cavan. Dilf. 2. 

 after page 1&6. Schreb. Gen. 114. Willd. Sp. PI. v. i. 

 8^9. Mart. Mill. Dift. v. 4. — Clafs and order, Pentandrla 

 Monogynia. Nat. Ord. Lur'ida, Linn. Solaneit, Juff. 



Gen. Ch. Cal. Perianth inferior, of one leaf, perma- 

 nent, divided half way down, into five unequal acute feg- 

 mcnts. Cor. of one petal, bell-ft\aped ; tube very (hort ; 

 limb inflated, plaited, five-cleft, longer than the calyx ; the 

 two upper fegments reflexed. Neftary a ftiort, mem- 

 branous, five-toothed cup, furrounding the germen. Stam. 

 Filaments five, very (hort, inferted into the teeth of the 

 neftary at the outfide ; anthers arrow-fhaped, converging. 

 Ptjl. Germen fuperior, roundifti, with two furrows ; ftyle 

 thread-fliaped, ftraight, rather longer than the ftamens ; 

 ftigma obtufe. Perk. Berry dry, nearly globular, of four 

 cells. Seeds two in each cell, roundifh, compreffed, rough, 

 one over the other. 



EIT. Ch. Corolla bell-ftiaped, irregular. Neftary with 

 five teeth, furrounding the germen, and bearing the ftamens. 

 Berry dry, of four cells, with two feeds in each. 



Obf. Cavanilles obferved one or two of the cells to be 

 occafionally abortive. 



I. T. ambrofiaca. Muflcy Triguera. Cavan. DiiT. 2. 

 t. A. Willd. n. I. ( Verbafcum Oftjeckii ; Linn. Sp. PI. 

 255. Willd. Sp. PI. v. I. 1006; excluding, from both, 

 the reference to Tournefort, and the laft-named place of 

 growth. Oftj. It. 52.) — Leaves decurrent, obovate, fer- 

 rated. Calyx villous. — Native of Spain, towards the coaft, 

 and of Salee in Barbary, flowering in the fpring. Root 

 annual. Stems fimple, ereft or decumbent, angular, leafy, 

 J fpan high. Leaves alternate, two inches long, fomewhat 



T R I 



hairy, coarfely ferrated, tapering at the bafe, and fomewhat 

 decurrent ; the upper ones fmallcr. Flo-wer-jlalls axillary, 

 in pairs, fingle-flowered, drooping. Calyx covered with 

 woolly hairs. Corolla deep violet, an inch wide ; nearly 

 black in the throat. Seeds blackifti, hard. The whole 

 plant, called in Spanifli yllmizqtiena, and Moradilla, has a 

 pleafant mufky fcent. It is fpoken of as pofleffing the 

 emollient narcotic virtues of Deadly Nightftiade, and Hem- 

 lock, being, like thofe plants, ufeful in cancers of the 

 breaft ; fo far at leaft as to allay the pain. 



2. T. inodora. Scentlefs Triguera. Cavan. as above. 

 Willd. n. 2. — Leaves fefiile, ovato-lanceolate, entire. Calyx 

 fmooth. — Found in Andalufia with the foregoing, and vul- 

 garly named Moradilla bldnque%ina. Differs from the firft in 

 the fmoothnefs of every part. The _/?oto«v are handfome, 

 drooping. Throat very pale violet, or yellowifli-white, with 

 five ftripes ; limb pale violet, or purple, with entire pointlefs 

 lobes. 



TRIGUEROS, in Geography, a- town of Spain, in the 

 province of Seville ; 8 miles N.N.E. of Moguer. 



TRIGYNIA, in Botany, from ifu-, three, and ymri, a 

 female, the n.ime of an order in many clafles of the Linnsean 

 artificial fyftem, diftinguiilied by the flowers having three 

 ftyles, piftils, or fefiile ftigmas. Of the latter. Viburnum 

 and Sambucus, in the fifth clafs, are inftances. The order 

 in queftion occurs in the ift, 2d, 3d, 5th, 6th, 8th, 9th, 

 loth, nth, 12th, and 13th clafles; in the 4th and 7th it 

 is wanting. Indeed in the 13th clafs, this order is but un- 

 certain, Delphinium and Aconitum, on which Linnaeus founded 

 it, being variable in the number of piftils. In the 1 2th clafs, 

 Icofandria, it forms fuch unnatural and troublefome diftinc- 

 tions, as to be much better aboliftied. See Pentagynia. 



TRIHILATiE, fo denominated from tres, tria, three, 

 and hilum, the fear of a feed, becaufe fome of the principal 

 genera are remarkable for the broad fears of their three 

 feeds ; the 25d natural order among the fragmenta of Lin- 

 nxus, ftanding between his Caryophyllei and Corydales, to 

 the latter of which only it has any, even the flighteft, 

 affinity. 



This is in itfelf but a heterogeneous afliemblage, em- 

 bracing feveral of Juffieu's orders, particularly the Sapindi, 

 Acera and Malpighite, as alfo his Melia. It confifts of three 

 feftions. In the firft are Melia, Trichilia, Guarea and Tur- 

 ma; to which Linnaeus was afterwards inclined to add C<- 

 drela and Swietenia. The fecond feftion confifts of Malpighia, 

 Bannijleria, Hirita, Triopteris, Acer and JF.fculus : and the 

 third, of Staphyka, Sapindus, Paulltnia, Cardiofpermum and 

 Trop£olum, to which Linnsus afterwards added Hippocratea, 

 more certainly belonging to the fecond feftion. 



Cavanilles, in his Diflertations on Monadelphous Plants, 

 has added many new genera to the Trihilatue ; but he is ex- 

 tolled beyond meafure by Gifeke in his edition of the Prt- 

 kaiones of Linnasus ; where an account is given, not only 

 of thefe genera, but of various others, confidered by Cava- 

 nilles .^s monadelphous, though contrary to the general 

 opinion. See Monadelpiiia. 



TRIHING, Thrihing, or Trithing, from the Saxon, 

 drihinge, an extent containing three or four hundreds, or 

 the third part of a fliire, or province. See TiTliiNG. 



Mr. Thorefby thinks the word ought to be written 

 thrithing. See Thorefb. Ducatus Leodenf. p. 85. 



Thefe trithings ftill fubfift in the county of York, where 

 by an eafy corruption they are denominated ridings. 



The word is alfo ufed for a court held within that cir- 

 cuit, which was the fame with what we now call a court-leet, 

 which is above a court-baron, and inferior to the county- 



court. 



TRIKALA, 



