Vol. III. _Physics._ First came general physics (1 book), then particular sciences (3 books). Liber i. _Communia Naturalium_, divided into 4 parts. MSS. Brit. Mus.: Royal 7 F vii. f. 84 (sec. xiii), _Liber Naturalium_. ‘Hoc est volumen naturalis philosophiae in quo traditur scientia rerum naturalium, secundum potestatem octo scientiarum naturalium quae enumerantur in secundo capitulo; et habet hoc volumen quatuor libros principales, Primum scilicet _De communibus ad omnia naturalia_; secundum _De Coelestibus_; tertium _De Elementis, mixtis, inanimatis_; quartum _De vegetabilibus et generabilibus_.’ (This MS. ends at the third part of the first book). Bodl.: Digby 70 (sec. xiv). _Communia Naturalium._ _Inc._ ‘Postquam tradidi grammaticam’ [Desinit ad init. cap. vii]. Cf. Digby 190, f. 29 (sec. xiv ineuntis). _De principiis naturae_; beginning illegible. Paris:--Bibl. Mazarine 3576; olim 1271, f. 1-90 (sec. xiv). ‘Incipit liber primus Communium naturalium Fratris Rogeri Bacon, habens quatuor partes principales, quarum prima habet distinctiones quatuor. Prima distinctio est de communibus ad omnia naturalia et habet capitula quatuor. Capitulum primum de ordine scientiae naturalis ad alias. (_Inc._) Postquam tradidi grammaticam secundum linguas diversas.’ Extracts printed by Charles, pp. 369-391. Libri ii, iii, iv. The special natural sciences, according to the Royal MS. just quoted, were treated in three books. They were seven[1353] in number, as Bacon enumerates them in the second chapter of the first part of the _Communia Naturalium_. ‘Praeter scientiam communem naturalibus, sunt septem speciales, videlicet perspectiva, astronomia judiciaria et operativa, scientia ponderum de gravibus et levibus, alkimia, agricultura, medicina, scientia experimentalis.’ Liber ii. (1) _Optics_ or _Perspective_ (a version of the _De multiplicatione specierum_). _Inc._ ‘Ostensum quippe in principio hujus Compendii Philosophiae.’ MSS. Brit. Mus: Royal 7 F vii. p. 221 (sec. xiii), fragment, called ‘Quinta pars Compendii theologiae’; and Addit. 8786, fol. 2 (fragment). [Cf. Bodl. Digby 183, fol. 49 (sec. xiv)?] See the references under _Tract. de multiplicatione specierum_. (2) _Astronomy_, or, _De coelo et mundo_. MSS. Oxford:--Bodl. Digby 76, f. 1 (sec. xiii), _Compendium Philosophiae_. _Inc._ ‘Prima igitur veritas circa corpora mundi est quod non est unum corpus continuum et unius nature.’ _Ibid._ fol. 36, _De corporibus coelestibus, sc. de zodiaco, sole, etc._ _Inc._ ‘Habito de corporibus mundi prout mundum absolute constituunt’ (cf. _Opus Minus_). Cf. Ashmole 393 I, f. 44 (sec. xv), ‘Veritates de magnitudine ... planetarum. Tractatus extractus de libris celi et mundi,’ etc. Also, Univ. Coll. 49, De corporibus coelestibus.