LAETUS

laetus, julius pomponius [giulio pomponio leto], (1425-1498), italian humanist, was born at salerno. he studied at rome under laurentius valla, whom he succeeded (1457) as professor of eloquence in the gymnasium romanum. about this time he founded an academy, the members of which adopted greek and latin names, met on the quirinal to discuss classical questions and celebrated the birthday of romulus. its constitution resembled that of an ancient priestly college, and laetus was styled pontifex maximus. the pope (paul ii.) viewed these proceedings with suspicion, as savouring of paganism, heresy and republicanism. in 1468 twenty of the academicians were arrested during the carnival; laetus, who had taken refuge in venice, was sent back to rome, imprisoned and put to the torture, but refused to plead guilty to the charges of infidelity and immorality. for want of evidence, he was acquitted and allowed to resume his professorial duties; but it was forbidden to utter the name of the academy even in jest. sixtus iv. permitted the resumption of its meetings, which continued to be held till the sack of rome (1527) by constable bourbon during the papacy of clement vii. laetus continued to teach in rome until his death on the 9th of june 1498. as a teacher, laetus, who has been called the first head of a philological school, was extraordinarily successful; in his own words, like socrates and christ, he expected to live on in the person of his pupils, amongst whom were many of the most famous scholars of the period. his works, written in pure and simple latin, were published in a collected form (_opera pomponii laeti varia_, 1521). they contain treatises on the roman magistrates, priests and lawyers, and a compendium of roman history from the death of the younger gordian to the time of justin iii. laetus also wrote commentaries on classical authors, and promoted the publication of the editio princeps of virgil at rome in 1469. see _the life of leto_ by sabellicus (strassburg, 1510); g. voigt, _die wiederbelebung des klassischen alterthums_, ii.; f. gregorovius, _geschichte der stadt rom im mittelalter_, vii. (1894), p. 576, for an account of the academy; sandys, _history of classical scholarship_ (1908), ii. 92. laevius (? c. 80 b.c.), a latin poet of whom practically nothing is known. the earliest reference to him is perhaps in suetonius (_de grammaticis_, 3), though it is not certain that the laevius milissus there referred to is the same person. definite references do not occur before the 2nd century (fronto, _ep. ad m. caes._ i. 3; aulus gellius, _noct. att._ ii. 24, xii. 10, xix. 9; apuleius, _de magia_, 30; porphyrion, _ad horat. carm._ iii. 1, 2). some sixty miscellaneous lines are preserved (see bahrens, _fragm. poet. rom._ pp. 287-293), from which it is difficult to see how ancient critics could have regarded him as the master of ovid or catullus. gellius and ausonius state that he composed an _erotopaegnia_, and in other sources he is credited with _adonis_, _alcestis_, _centauri_, _helena_, _ino_, _protesilaudamia_, _sirenocirca_, _phoenix_, which may, however, be only the parts of the _erotopaegnia_. they were not serious poems, but light and often licentious skits on the heroic myths. see o. ribbeck, _geschichte der romischen dichtung_, i.; h. de la ville de mirmont, _etude biographique et litteraire sur le poete laevius_ (paris, 1900), with critical ed. of the fragments, and remarks on vocabulary and syntax; a. weichert, _poetarum latinorum reliquiae_ (leipzig, 1830); m. schanz, _geschichte der romischen litteratur_ (2nd ed.), pt. i. p. 163; w. teuffel, _hist. of roman literature_ (eng. tr.), § 150, 4; a convenient summary in f. plessis, _la poesie latine_ (1909), pp. 139-142. laevulinic acid ([beta]-acetopropionic acid), c5h8o3 or ch3co·ch2·ch2·co2h, a ketonic acid prepared from laevulose, inulin, starch, &c., by boiling them with dilute hydrochloric or sulphuric acids. it may be synthesized by condensing sodium acetoacetate with monochloracetic ester, the acetosuccinic ester produced being then hydrolysed with dilute hydrochloric acid (m. conrad, _ann._, 1877, 188, p. 222). ch3·co·ch·na ch3·co·ch·ch2·co2r | --> | -->ch3coch2·ch2·co2oh. co2r co2r it may also be prepared by heating the anhydride of [gamma]-methyloxy-glutaric acid with concentrated sulphuric acid, and by oxidation of methyl heptenone and of geraniol. it crystallizes in plates, which melt at 32.5-33° c. and boil at 148-149° (15 mm.) (a. michael, _jour. prak. chem._, 1891 [2], 44, p. 114). it is readily soluble in alcohol, ether and water. the acid, when distilled slowly, is decomposed and yields [alpha]- and [beta]-angelica lactones. when heated with hydriodic acid and phosphorus, it yields n-valeric acid; and with iodine and caustic soda solution it gives iodoform, even in the cold. with hydroxylamine it yields an oxime, which by the action of concentrated sulphuric acid rearranges itself to n-methylsuccinimide [ch2·co]2n·ch3.