Divine Things, Politics, and Heaven are only a few of the titles of the 220 works ascribed to him by Diogenes Laertius.8
In fact, so varied and enormous was the output of both Theophrastus and Aristotle that many treatises written by their pupils have no doubt been included under their names; but, because of similarities in style and thought, such works can rightly be considered productions of the Peripatetic school and for convenience < be ascribed to the masters. The treatise On Stones has sometimes been placed in this category, for in style it is more like a set of student's notes than a finished scientific work. Certain of its passages, such as the one in section 68 containing an illustrative story, are obvious abridgments that seem to be mere memoranda written to recall more detailed information. Hence it seems probable that the treatise, as we now have it, is only a set of notes taken down by some student while listening to lectures given by Theophrastus. It is also possible, on the basis of the same internal evidence, that we have before us the personal lecture notes of the master himself. Whether the treatise in its present form is a set of notes taken at lectures or previously written for lectures, it may safely be assumed to represent the actual views of Theophrastus, and he may reasonably be considered the real author.
Internal evidence indicates that the treatise was written near the end of the fourth century B.C., well within the lifetime of Theophrastus. This evidence appears in section 59 in the form of a statement about the time of the discovery by a certain Kallias of a process for refining cinnabar. The validity of this evidence is discussed at length in the notes on that section of the Commentary.
There are comparatively few manuscripts, editions, and translations of the works of Theophrastus, and the treatise On Stones has appeared even less often than some of his other works. Only three codices are known to contain it—namely, Vaticanus 1302, Vaticanus 1305, and Vaticanus Urbinas 108—and the versions differ little from each other. Moreover, only two of them are complete, as Vaticanus 1305 ends in the middle of section 43. According to Schneider, these codices were collated by Brandis, who
8 By actual count there are 226 such titles, but six of these are bracketed as probable repetitions by R. D. Hicks, ed., Diogenes Laertius, Lives of Eminent Philosophers (Loeb Classical Library, London and New York, 1925), Vol. I, pp. 488-502.
