Complete Works of Euclid, Vol. 7 (Optics and Catoptrics)

XVI PROLEGOMENA.

...differences, of which there will be a place to speak in chapter III. If, setting these interpolations aside for a time, we compare the translation with the Greek manuscripts, it is apparent that it relies upon a Greek manuscript that, if you look at the sum, is similar to ours; for the same errors occur, such as p. 5, 18; 7, 5; 13, 11; 15, 6; 17, 2, 9; 19, 4—5; 25, 3, 5; 67, 16; 69, 13; 81, 11; 83, 4; 89, 5; 95, 1; 97, 6, 17; 103, 7; 107, 3, 4 (cf. p. 105, 15); 109, 7; 115, 3—4. It rarely has a more amended reading, such as p. 29, 11; 115, 2; 117, 14, and perhaps p. 31, 2 (ὡς — λέγεται p. 30, 3 omitted); p. 31, 5 (τῶν δέ — πλευραὶ p. 30, 7—8 omitted); p. 71, 28 (perhaps write διὰ τοῦ κέντρου αἱ AB, ΓΔ p. 70, 19); p. 81, 13 (πᾶσαι ἄνισοι p. 80, 17?); p. 89, 8 (for ΓEA p. 88, 8 perhaps ΓEH); p. 97, 20 (for AE p. 96, 23 better EA). The gaps at p. 37, 2; 39, 7; 77, 12; 79, 16; 87, 21; 99, 19 are perhaps due to the scribe. It rarely conspires with V (p. 11, 12; 19, 8; 27, 15; 31, 6, 14; 39, 5; 47, 11; 49, 5; 71, 1; 83, 9; 89, 9?); on the contrary, there is the highest agreement with the other class (p. 7, 16, 18; 9, 11, 24; 11, 12, 19; 13, 12; 15, 21; 17, 13, 20; 19, 4, 5, 17; 21, 22; 25, 7; 27, 9, 14; 33, 3; 35, 14; 37, 5, 7, 15; 39, 3, 16; 41, 2, 4, 7; 43, 12; 45, 3; 47, 7, 8; 53, 6, 12; 55, 12; 57, 11; 63, 2, 17, 18, 21; 65, 5, 6, 8, 10, 11, 12, 15; 67, 3, 6, 7, 15; 69, 2, 3, 8; 71, 10; 75, 4; 79, 6; 83, 15; 85, 5; 89, 7, 9; 91, 12, 14; 97, 15, 16; 101, 19; 103, 9; cf. p. 25, 16; 35, 16; 41, 1; 103, 17; with v alone p. 105, 7, with Vat. alone p. 61, 6), even in open mistakes (p. 71, 16; 73, 6; 75, 9; 79, 4; 101, 6; 105, 15; 107, 3, 4; 115, 8; cf. p. 5, 13; 15, 8; 97, 14). In this great constancy, it is memorable that in not so few places it also agrees with m from the first class (p. 27, 14; 37, 11; 67, 18; 69, 12; 75, 7; 79, 4), sometimes in more serious errors, such as p. 37, 13; 83, 8; 99, 10, 22. We shall see about its origin in chapter III.

II.
On the manuscripts of the Theonine Optics.

First, let us enumerate the manuscripts besides Vv, which contain both the Optics of Theon and the Catoptrica.

1. cod. Vatic. Gr. 192, 14th century, see above.
2. cod. Ottobon. Gr. 102, paper, 16th century, from the manuscripts of Johannes Angelus, Duke of Altaemps. Contains the Catoptrica, Optics, Heliodorus, Arrian on Epictetus.
3. cod. Angelic. C 2, 9, paper, 15th century; see Om Scholierne til Euklids Elementer p. 34.