By the close of 1267 the work was done.

The "greater work," itself in modern form a closely-printed folio, with its successive summaries and appendices in the "lesser" and the "third" works (which make a good octavo more), were produced and forwarded to the Pope within fifteen months.
[Sidenote: The Opus Majus] No trace of this fiery haste remains in the book itself.

The "Opus Majus" is alike wonderful in plan and detail.

Bacon's main purpose, in the words of Dr.Whewell, is "to urge the necessity of a reform in the mode of philosophizing, to set forth the reasons why knowledge had not made a greater progress, to draw back attention to sources of knowledge which had been unwisely neglected, to discover other sources which were yet wholly unknown, and to animate men to the undertaking by a prospect of the vast advantages which it offered." The developement of his scheme is on the largest scale; he gathers together the whole knowledge of his time on every branch of science which it possessed, and as he passes them in review he suggests improvements in nearly all.

His labours, both here and in his after works, in the field of grammar and philology, his perseverance in insisting on the necessity of correct texts, of an accurate knowledge of languages, of an exact interpretation, are hardly less remarkable than his scientific investigations.