s on the
scholastic philosophy, with the view of collecting and publishing such
of its monuments as have escaped the diligence of scholars, or the
ravages of time, has lately made the discovery in the library at Douay
of a copy of an inedited MS. of Roger Bacon, entitled _Opus Tertium_, of
which but two or three other copies are known to exist; and has taken
occasion, in some elaborate critiques, to enter, at considerable length,
into the history and character of Roger {394} Bacon and his writings.[1]
The following is a summary of part of M. Cousin's observations.

The _Opus Tertium_ contains the author's last revision, in the form of
an abridgment and improvement, of the _Opus Majus_; and was drawn up at
the command of Pope Clement IV., and so called from being the _third_ of
three copies forwarded to his holiness; the third copy being not a
_fac-simile_ of the others, but containing many most important
additions, particularly with regard to the reformation of the calendar.
It also throws much light on Bacon's own literary history and studies,
and the difficulties and persecutions he had to surmount from the
jealousies and suspicions of his less-enlightened contemporaries and
rivals. The _Opus Tertium_, according to the sketch given of its
contents by Bacon himself, is not complete either in the Douay MS. or in
that in the British Museum, several subjects being left out; and, among
others, that of Moral Philosophy. This deficiency may arise, either from
Bacon not having completed his original design, or from no complete MS.
of this portion of his writings having yet been discovered. M. Cousin
says, that the _Opus Tertium_, as well as the _Opus Minus_, is still
inedited; and is only known by what Jebb has said of it in his preface
to the _Opus Majus_. Jebb quotes it from a copy in the Cottonian
Library, now in the British Museum; and it was not known that there was
a copy in France, till M. Cousin was led to the discovery of one, by
observing in the Catalogue of the public library of Douay, a small MS.
in 4to. with the following title, _Rog. Baconis Grammatica Graeca_.
Accustomed to suspect the accuracy of such titles to MSS., M. Cousin
caused a strict examination of the MS. to be made, when the discovery
was communicated to him that only the first part of the MS. consisted of
a Greek grammar, and that the remaining portion, which the compiler of
the Catalogue had not taken the trouble to examine, consisted of many
frag