now 'Opus Tertium,' and to forward them to Clement. Rather we may conjecture that he began and carried out his plan of detailed treatment, so as to form a complete body of scientific exposition, and that the several portions were indifferently connected with the 'Opus Tertium' and with the later work, the 'Compendium Philosophiæ,' of which the introduction dates from 1271. For the indications point to a substantial identity of content in the two supposed systematic works. Under the one, the so-called 'Opus Tertium,' there appear to fall (1) grammar and logic, (2) mathematics, (3) physics, (4) metaphysics and moral philosophy; under the other, the 'Compendium Philosophiæ,' (1) grammar, (2) logic, (3) mathematics, (4) physics, (5) alchemy, (6) experimental science. The identity of contents explains the difficulty of assigning the extant fragments to the one or to the other, and probably the definite designations we adopt for the two works do not fairly represent anything in Bacon's plan. Of the treatment of grammar, some part remains in the manuscript on Greek grammar in University College, Oxford. Of mathematics, the discussion of the general ideas, 'Communia Mathematica,' is contained in the manuscripts, Brit. Mus. Sloane Coll. 2156, and Bodl. 1677. Of physics, a very important fragment, treating of the fundamental ideas, 'Communia Naturalium,' exists in no fewer than four forms, in the Mazarine Library, Paris, 1271, in the Brit. Mus. Royal Lib. 7 F. vii., in the Bodleian, 1671, and in the library of Univ. Coll. Oxford; the publication of this manuscript, which contains Bacon's treatment of the most important notions of scholastic thinking, is a desideratum. Of the metaphysics, a small portion is found in the Bodleian, 1791, and more in the Biblioth. Imp. at Paris, No. 7440. A more detailed treatment of physics, by its link-expressions designed to form part of the 'Compendium Philosophiæ,' is contained in the Brit. Mus. Addit. MSS. 8786. Of the latest work of Bacon, the 'Compendium Studii Theologiæ,' date 1292, some few fragments, from which the plan of the whole may be gathered, are contained in the British Mus. 7 F. vii. fo. 153, and 7 F. viii. fo. 2, and in the library of Univ. Coll. Oxford (see Charles, pp. 409-16). The British Museum (Royal Lib. 7 F. viii. fo. 99-191) has also a complete manuscript of an early writing, the 'Computus,' on astronomy and the reformation of the calendar, the date of which, as given in the manuiscript itself, is 1263.
It is much to be desired that a more thorough and detailed study of the known manuscripts and a more extensive search for others which doubtless exist should be undertaken. Some portions are in a condition suitable for publication, and it is wellnigh an obligation resting on English scholars to continue the good work begun by the late Professor Brewer. Bacon's works possess much historical value, for his vigorous thinking and pronounced scientific inclinations are not to be regarded as abnormal and isolated phenomena. He represents one current of thought and work in the middle ages which must have run strongly though obscurely, and without a thorough comprehension of his position our conceptions of an important century are incomplete and erroneous.
[Of the earlier works in which Bacon was dealt with at large or incidentally, of Wadding, Cave, Oudin, Leland, Bale, Pits, Tanner, and others, a copious list will be found in the Histoire Littéraire de la France (xx. 227-52); the most valuable recent studies are those of Brewer (preface to E. B. Opera Inedita, London, 1859) and E. Charles (Roger Bacon, sa Vie, ses Ouvrages, ses Doctrines, d'aprês des testes inédits, Paris, 1861), whose work is a model of industry, skill, and intelligence; summaries, mainly of these two authorities, are to be found in Siebert, Roger Bacon, Marbiurg, 1861; Saisset, Revue des deux Mondes, 1861; Westminster Review, January and April 1864; Held, R. B.'s praktische Philosophie, Jena, 1881. Laying greater stress on the scholastic elements in Bacon's work, and somewhat depreciatory in tone, are L. Schneider, Roger Bacon, Augsburg, 1873, and K. Werner, Die Psychologie, Erkenntniss-und Wissenschafts-theorie des R. B., and Die Kosmologie und allgenieine Naturlehre des R. B., Wien, 1879. The popular legend, represented by the Famous Historie of Fryer Bacon, London, 1615 (reprinted in Thoms's Early Prose Romances, iii.), has been turned to good account in English literature; see Terilo's A Piece of Friar Bacon's Brazen Heade's Prophesie, 1604, reprinted in Percy Society Publications, vol. xv., 1844, and Greene's Friar Bacon and Friar Bungay, 1587 or 1588. On Greene and on the references in other literary pieces to Roger Bacon, see the Introduction and Notes to Ward's Old English Drama, 1878.]
BACON, THOMAS (fl. 1336), judge, was most probably a member of the same family that produced Sir Nicholas and the great Francis Bacon; for he was possessed of property at Baconsthorpe and other places in Norfolk, which later belonged to the lord chancellor. He was a justice of the Common Pleas in the early years of Edward III's reign, and in this capacity was knighted by that king (Dugdale, Origines, 102). According to Foss, he was raised to the King's Bench in 1332, and certainly appears in this year as one of those appointed to try and
