Dicta fratris Rogerii Bacon in libro sex scienciarum in 3{o} gradu sapiencie, ubi loquitur de bono corporis et de bono fortune et de bono et honestate morum. (_Inc._) In debito regimine corporis et prolongatione vite ad ultimos terminos naturales ... miranda potestas astronomie alkimie et perspective et scienciarum experimentalium. Sciendum igitur est pro bono corporis quod homo fuit immortalis naturaliter ... (_Expl._) ut fiant sublimes operaciones et utilissime in hoc mundo, etc. Charles identifies the _Liber sex scientiarum_ with the _Opus Minus_; but this passage does not occur in the extant portion of the _Opus Minus_ which deals with the same subject and expresses the same ideas (_Opera Ined._, p. 370 _seq._). It seems probable therefore that this passage is an extract from the section on Alchemy in vol. iii. of the _Compendium Philosophiae_. Vol. I. _Grammar and Logic._ A portion of this has been edited by Brewer, _Opera Ined._, pp. 393-519, under the title _Compendium Studii Philosophiae_. It was written in 1271, and contains an introduction on the value of knowledge and the impediments to it, and the beginning of a treatise on grammar. MS. Cott. Tiberius C. V. (sec. xiv). Two other treatises on grammar by Roger Bacon are extant, and probably formed part of the _Comp. Phil._[1352]: (1) _Inc._ ‘Primus hic liber voluminis grammatici circa linguas alias a Latino.... Manifestata laude et declarata utilitate cognitionis grammatice’ (chiefly on Greek grammar). MSS. Brit. Museum: Cotton Jul. F viii. f. 175 (sec. xv), a fragment. Oxford:--Corpus Christi Coll. 148 (sec. xv); Univ. Coll. 47 (sec. xvii). Douai, 691 § 1 (sec. xvii), copied from Univ. Coll. MS. 47. (2) _Inc._ ‘Oratio grammatica autem fit mediante verbo.’ ‘Explicit summa de grammatica magistri Rogeri Bacon.’ MS. Cambridge:--Peterhouse, 1, 9, 5, James 3 (sec. xiv). Vol. II. _Mathematics_; 6 books: i. _Communia mathematicae_, ii-vi. Special branches of mathematics. Liber i. _Inc._ ‘Hic incipit volumen verae mathematicae habens sex libros. Primus est de communibus mathematicae, et habet tres partes principales.’ MSS. British Museum: Sloane 2156, f. 74-97 (sec. xv), ending in the second part of the first book. Bodl.: Digby 76, fol. 48 (sec. xiii), containing the remainder of the first book (?). _Inc._ ‘Mathematica utitur tantum parte.’ Libri ii-vi. An extant fragment of a commentary on Euclid by Bacon may have belonged to this part; in _De Coelestibus_ (_Comp. Phil._ vol. iii.) he often refers to his commentary on the Elements of Euclid (Charles, p. 85). MS. Digby 76, f. 77-8 (sec. xiii). A treatise, _De laudibus mathematicae_, expressing the same ideas as Part iv. of the _Opus Majus_, may have been intended as an introduction to this volume. MS. Royal 7 F vii. fol. 141-152: cf. Digby 218, f. 98.