I S N 



media, the capital of Dkhynia ; 4J miles E.S.E. of Con- 

 ftantinople. N. lau 40' 39'. E. long. 29 34'. 



IsMiD, a town of Albtic Turkey, in Caramania ; 24 

 miles E S E. of Cogni. 



ISMIL, a town of Afiatic Turkey, in Caramania ; 30 

 miles E. of Cogni. 



ISMOKIL, a fmall ifland on the E. fid- of the gulf of 

 Bothnia. N. lat. 63 ' 16'. E. long. 21 jo'. 



ISN'AGAR, or Isnajar, a town of Spain, in the pro- 

 vince of Cordova, 10 milfs S. of Lueena. 



ISNARDI, in Biography, according to M. Laborde, 

 " after iinging, in his youth, on the Sage with fuccefs, 

 quitted the theatre, and ftudied compofitioj and poetry. 

 After which he publifhed fonnets, madrigals, and even (hort 

 dramas, fct to mufic by himfelf. His works have been often 

 reprinted." Now if Waltlier's dates are correiS, and he 

 gives authorities for them, Ifnardi inuft have fang with fuc- 

 cefs on the ftage before the lyric ftage or operas had ex- 

 iilence ; but we are unable to lind a mufician of this name. 



ISNARDIA, in Botany, was fo named by Linnjeus, in 

 honour of M. Antoine Danti difnard, member of the Aca- 

 demy of Sciences, in the jSIemoires of which academy may 

 be found feveral of his tracts on botany, pubhlhed between 

 the vears .1716 and 1726 — Linn. Gen. 61. Schreb. 84. 

 Willd. Sp. PI. V. I. 6S0. Mart. Mill. Dicl. v. 2. Ait. Hort. 

 Kew. ed. 2. v. i. 266. JufT. m. Laaiarck. lUuftr. t. 77.— 

 Clafs and order, Tetrandna Monogynla. Nat. Ord. Calycan- 

 tbemt, Linn. SalicariiS, Jufl". 



Gen. Ch. Cal. Perianth fuperior, bell-diaped, perma- 

 nent, divided into four, flightly fpreading fegments. Cor. 

 .>^one. Slam. Filaments four, (horter than the calyx, one 

 placed within each fegment of it ; anthers ilmple. Ptji. 

 Germen inferior ; ftyle cyhndrical, longer than the ftamens ; 

 ftigma capitate. Peric. Capfule fquare, of four cells, 

 crowned by the calyx. Siifds numerous, oblong. 



Eir. Ch. Corolla none. Calyx four-cleft. Capfule of 

 four cells, crowned by the calyx. 



Obf. Linnseus has obferved, in a MS. note to his own 

 copy of the Genera Plantarum, that the bafe of the calyx 

 is furniflied with two awl-(haped brafteas adhering clofely 

 together. 



I. 1. palujlrls. Linn. Sp. PI. 175. (Glaux major pa- 

 luftris, flore herbaceo ; Bocc. Muf. 105. t. 84. f. 2.) A 

 native of rivers in France, Ruffia, Jamaica, North America, 

 &c. It flowers in July, and was Hrft introduced at Kew 

 by Dr. Fothergill, in 1776. — " In general appearance this 

 plant greatly reiembles Peplh Portulaca. It is creeping and 

 floating. Flo'wers axillary, oppofite, feflile, green." — Leavet 

 obovate, wedge-ihaped at the bafe, veined and fmooth. 

 .9fc(£r brown. — S.vartz has defcribed a plant in his Fl. Ind. 

 Occ. v. I. 273, under the name of Ludiuigta repens, which 

 he fays differs only from Ifnardta palujlrh in being furniflied 

 ■with petals. 



ISNARI, Paolo, of Ferrara, in Biography, a difciple 

 of the celebrated muflcian Manara, maeilro di cappella of 

 the Duomo in that city, and a voluminous compofer of 

 church raullc, flouriflied in the latter end of the fixteenth 

 century. In 1 j6^, he publifhed his " Cantus Hebdomadx 

 Sanftae," or Mufic for Paffion Week: in 156S, fix-part 

 mafles : in 1578, the Vefper pfalms in three parts, and three 

 Magnificats in four parts. This laft work was reprinted at 



Milan, I ygo. 

 ISNEl ' 



^LLO, in Geography, a town of Sicily, in the valley 

 ofDcmona; 13 miles S. of CefaU. 



ISNIK, a town of Afiatic Turkey, in Natolia, fituated 

 on a lake of the fame name, called by the ancients Afcanius, 

 that abounds with filh, and that communicates with the fea 



I S O 



of Marmora. The chief article of its trade is filk. It is 

 the fee of a Greek archbifliop, though it contains fcarcely 

 300 houfee. It was anciently called " Nice," and famous 

 for its council ; 60 miles E. of Conftantinople. N. lat. 40"^ 

 16'. E. long. 29^ jo'. 



ISNY, or YsNi, a town of Germany, lately imperi.ll, 

 fituated in the Algau, betwixt the counties of Holieneck 

 and Trauchburg, and the lordfliip of Eglof. The magif- 

 trates and greateft number of the citizens are Lutherans. 

 It has often fuffered by fire ; 40 miles S. of Ulm. N. lat. 

 47' 45'- E. long. 9- 58'. 

 _ ISOCHRONAL, or Isochronous, is applied to fuch 

 vibrations of a pendulum, as are performed in equal times. 



Of which kind are all the vibrations or fwings of the 

 fame pendulum, whether the arcs it defcribes be longer or 

 fiiorter ; for when it defcribes a fliorter arc, it moves fo 

 much the flower ; and when a long one, proponionably 

 faller. See Pendulum. 



I.socHRON.\L Lint, is that wherein a heavy body is fup- 

 pofed to defcend without any acceleration. 



Leibnitz, in the Act. Erud. Lipf. for April 1689, has a 

 difcourfe on the llnea Ifochrcna, in which he fliews, that a 

 heavy body, with a degree of velocity acquired by its defcent 

 from any height, may defcend from the fame point by an 

 infinite number of ifochronal curves, which are all of the 

 fame fpecies, differing from one another only in the magni- 

 tude of their parameters ; fuch as are all the quadrato- 

 cubical paraboloids, and confequently fimilar to one another. 

 He fliews alfo how to find a Hne, in which a heavy body 

 defcending, fliall recede uniformly from a given point, or 

 approach uniformly to it. See Cycloid. 



ISOCHRONOUS Parcels, \y^MuJlc. Mr. John Holden 

 labours in his " Effay towards a rational Syftem of Mufic," 

 to eftablilh it as a principle, that " there is a certain propen- 

 fity in our mind to be fubdividing the large numbers (of 

 equal and equidifl:ant objecls) into fmaller equal parcels : or, 

 as it may be jullly called, compounding the large numbers of 

 feveral fmall faSors, and conceiving the whole by means of 

 its parts," p. 288. " Seven, we conceive, as two threes dif- 

 joined, and one in the middle ; five becomes two twos dif- 

 joined, and one in the middle," p. 289 ; and again, p. 305, 

 " we readily conceive five by its affinity to four, and feven 

 by its afiinity to fix," p. 292. «' Among the ifochronous 

 fingle vibrations of mufical founds, the mind naturally 

 feeks to conllitute ifochronous compound parcels." — " The 

 fixe or magnitude of a mufical interval is eflimated bv 

 the InequaUty of the ifochronous parcels of vibrations of 

 its two terms ; and in proportion as their ifochronous 

 parcels differ more from cquahty, the included interval be- 

 comes greater," p. 327. The above axtraiits Ihcw the 

 nature and ufes to which this author attempts to apply his 

 ifochronous parcels of vibrations ; in which we can fcarcely 

 admit hun to have been more fucccfsful, than in the appli- 

 cation of the Grave Harmonics (fee tliat article), or Tar- 

 tinian founds, to accounting for the conftitution of the mu- 

 fical fcale ; tlie incongruous fyftem of intervals to which 

 thefe fancies lead, will be feen in our article Holden 's 

 Syjlem of liliiftcal Intervals. 



ISOCRATES, m Biography, a celebrated Greek rheto- 

 rician, was born at Athens about the year 436 B. C. He 

 received a good education, but his father, being ruined by 

 the Peloponnefian war, left him no other inheritance. He 

 had iludied under Gorgias, Prodicus, and other great mailers 

 of eloquence, but the weaknefs of his voice, and his want of 

 a proper degree of confidence, prevented him from ex- 

 ercifing the talent of fpeaking in public. He employed 

 himfelf, therefore, in corapofing difqourfes in his clofet, and 



