Three Books on Harmonics by Claudius Ptolemy

...from the munificence of the Most Honorable William, Earl of Pembroke, then Chancellor of the University of Oxford. This codex, as I conjecture from the paper, the method of binding, and the handwriting itself (written with a reed, not a quill, as is evident), and the form of the characters, had been acquired from Greece; it is the most ancient of all those I use.

I treat G and I likewise as one. I. was indeed (as is clear from the memorial note attached) the property of William Laud, Archbishop of Canterbury and Chancellor of the University of Oxford, in the year of our Lord 1638, and was donated by him to St. John's College, Oxford. I received it for use from its library (through the favor of the egregiously learned man, William Levinz, Doctor of Medicine, Professor Royal of the Greek language, and most worthy President of that same college). It is a very beautifully transcribed book (though not of great antiquity) and from a not-bad exemplar. I received the G codex on loan from Thomas Gale (Doctor of Sacred Theology and most learned Master of St. Paul's School, London), which had been, as I understand, transcribed from I (the St. John's codex) not many years ago. Therefore, where it disagrees with I (due to a scribe's error), I have not deemed it necessary to delay the reader.

To codex I, there were attached throughout (and from there transcribed into G) scholia (partly marginal, partly interlinear) by an uncertain author (which perhaps someone had added to his own copy for his own use), but which can be omitted without great loss; these I have decided to omit. The same applies, sometimes, to codices A, B, and C.

As for the K codex, I do not know whose it was or who it belonged to. But I consider it to be the one, whoever he was, with whom codex I had been compared; and from that, variant readings were added to its margins. These, indeed, not rarely, but not always, agree with codex C.

S also belonged to Savile and is preserved in the Savilian Mathematical Library. But it is incomplete, reaching no further than the first book, and barely to its end.

I received the beautifully transcribed codices V and O for use from the library of the most learned man, Isaac Vossius (who shared them willingly), and therefore I assigned them the first two letters of the name Vossianus. But this was late, namely, after the printers had reached chapter 12 of book 2. Hence, in my notes before that chapter, there is no mention of them; but only from the beginning of that chapter to the end of the book. However, I compared both with the proofs already printed (and I have added their variant readings to the end, so that nothing should seem lacking). I find hardly any variation in them from ours (that is of any moment) which I had not already noted from one of the other codices. And indeed, codex V (which seems the older of the two, transcribed, as is hinted at the end, in the year 1557) agrees almost everywhere with the aforementioned Baroccian C, so that there is no doubt that both were derived from the same source. And codex O similarly agrees with codex I (from which G was also transcribed) and has written in the margin almost the same variant readings that I previously mentioned as being transcribed from K (except that codex O sometimes incorporates some of these into the text), so that there is no doubt that this was also derived from the same source as I. But the scholia I mentioned as appearing in I and G are not found here.

Finally, I happened upon codex D, which is among the Baroccian codices, number 41 (to which I therefore assigned the letter D, so that it might be compared with the other Bodleian ones, ABC). It is a MS commentary by Porphyry on a portion of these books (namely, from the beginning to the end of chapter 7 of book 2), and it often has the text of Ptolemy (up to that point) inserted piece by piece (especially in the opening chapters). But I discovered it too late, not before the printers had reached the final two leaves of Ptolemy...