Basilides of Tyre

Basilides of Tyre (Ancient Greek: Βασιλείδης) was a mathematician, mentioned by Hypsicles in his prefatory letter of Euclid's Elements, Book XIV.

Basilides letter is part of the supplement taken from Euclid's Book XIV, written by Hypsicles.

[2] Basilides of Tyre, O Protarchus, when he came to Alexandria and met my father, spent the greater part of his sojourn with him on account of the bond between them due to their common interest in mathematics.

But I myself afterwards came across another book published by Apollonius, containing a demonstration of the matter in question, and I was greatly attracted by his investigation of the problem.

Now the book published by Apollonius is accessible to all; for it has a large circulation in a form which seems to have been the result of later careful elaboration.