Last week, I ventured over to the Royal Society to see Michael Hunter give an excellent talk about just one image: the iconic and much reproduced frontispiece to Thomas Sprat's History of the Royal-Society of London (London, 1667).
What I hadn't realised is that the image, which was designed by John Evelyn and engraved by Wenceslaus Hollar, wasn't meant for Sprat's work at all. Rather, it was originally intended for another work in defence of the Society being planned in 1664 by John Beale. Beale was going to call his work 'Lord Bacon's Elogies' and asked Evelyn to come up with an emblematic image. But once Sprat's work was known to be imminent, Beale abandoned his plans and suggested that the frontispiece go into Sprat's book. That's why it's had to be folded to fit into many copies, and also why not all copies of Sprat's history contain the image. It also presumably explains why the image doesn't always mirror what Sprat wrote.
Michael's talk traced the lineage of Evelyn's iconography - including a very striking borrowing of an image by Nicolas Chaperon - and talked about the various instruments and other items placed around the central group. In general, Evelyn illustrated instruments that symbolised the latest work being done by members - hence an air pump, 60-foot telescope, etc. For us, what's interesting is that three of them seem to be instruments for navigation and finding longitude:
They include an observing instrument with a rotating mirror, designed by Robert Hooke, a second shipboard observing instrument and a triangular sea-clock (about which I'll say more in due course).
Some of the other instruments remain a bit of a mystery, however, including a box-like item, something that may be for lens polishing (or not) and a roundish object on a table or slope:
Michael's hoping to write the whole thing up, so any suggestions would be welcome.