Engraving of a large reflecting telescope, and a projection of the transit of Venus. This diagram, entitled "An Apparatus adapted to the Reflecting Telescope for shewing The Transit of Venus", appeared in Benjamin Martin's "The Young Gentleman and Lady's Philosophy", published between 1755 and 1763 in the General Magazine and aimed at explaining astronomical principles to amateur astronomers. Transits of Venus across the disk of the Sun are among the rarest of planetary alignments.

- Image ID: T96KTY