A summary of the life and work of John Perdrix will be presented. John Perdrix also had a deep interest in the Great Melbourne Telescope (GMT). In view of the pending excursion to see the GMT and to emphasize the interest that John developed in the instrument, a discussion of the optical configuration of the GMT and the reasons behind some of the decisions made at the time of design will be put forward. At the time of the construction of the GMT well known testing techniques were not used but Thomas Grubb developed some innovative optical testing techniques. The telescope had a very long focal length and huge eyepieces were manufactured to obtain a reasonable magnification. The eyepieces, the secondary mirrors and other ancillary optical components will be discussed.