As far as I know sundials were not used in navigation, unless you call an astrolabe or quadrant a sundial. These were the old instruments used in navigation. Finding North using sundials isn't very accurate, especially not between 10:00 and 14:00. The farther the time is away from noon the more acurate it can be done. However if you want to do that on a (sailing)ship you need a very stable platform that remains perfectly horizontal. If not your horizontal sundial will be of no use. I have never seen a stable horizontal platform on a sailing ship except during periods of no wind and no waves at all (this is very seldom at sea).
Thibaud Taudin-Chabot [EMAIL PROTECTED] At 10:59 09-09-96 PDT, you wrote: >Are there references to the use of sundials in navigation? >In the days before magnetic variation was mapped, they must have been useful >(with the limitations of stability that a dial on board a ship would have.) >No doubt travellers on land used them, are there special types that >developed for this purpose? >>Also, does anyone know how accurately these dials are at orienting to >>north? They seem to have the advantage that they don't have to be >>adjusted for magnetic declination and that they aren't affected by >>other magnetic fields. (And of course the obvious disadvantage that >>they must have sun in order to work.) So, they seem like they would >>be a great companion to a compass. >\\\\\\\\\\\\\\\\\\\\//////////////////// > Peter Abrahams [EMAIL PROTECTED] >the history of the telescope, the microscope, > and the prism binocular > >
