A Mayer odyssey (part 3)

24 Sep 2011

To put your minds at rest, I have been attempting to do a bit of research on this trip too. This has included going to archives in Göttingen and Hannover to look at letters relating to the years of lobbying and negotiation - between Göttingen and London - that had to happen before Tobias Mayer, or rather his widow, was finally awarded £3,000 for his contribution towards making the lunar distance method possible at sea.

Funnily enough, most of the stuff I looked at was in German and pretty indecipherable (to me) due to the handwriting and my own lack of German skills, although I did come across some letters in English, French and Latin as well. I've ordered lots of copies, so we'll have plenty to work on, but a couple of things caught my attention immediately.

One thing I'm still trying to piece together a bit more, for instance, is Christopher Irwin's marine chair, and I'm pretty sure I saw it described in one letter as 'Erwin's Easy Chair', which makes it sound even more marvelous. I hope I'm not disappointed when I look at the copy again.

Another letter (in French) was from Mayer's widow, Marie Victoire, to Lord Grenville. It's an attempt to persuade Grenville to help her get the reward her late husband's work merited. The bit that caught my attention was a passage that seems to claim that a repeating circle of Mayer's design was used for longitude determinations by lunar distance on a voyage to 'Arabia' begun in 1761 by Carsten Niebuhr. It is well known that Niebuhr carried out lunar distances, but the other evidence suggests that this was with an octant. It may well be that she was wrong about the instrument used. It is more likely, for instance, that she was thinking of the 'astrolabium', a circular surveying instrument based on Mayer's repeating principle, with which Niebuhr made a few measurements (which was something Ivan Tafteberg Jakobsen talked about at the conference in Kassel). In any case, it's got me wanting to check things out a bit more.