NavList:

Brian Walton wrote: The Barker box sextant you have, with telescope, seems a good candidate for the sextant Chichester used crossing the Tasman.

Brian.  Do I understand you’re coming round to the idea that Chichester used a box sextant and not a marine sextant over the Tasman Sea?  Did you find a more specific reference than Hughes History of Air Navigation?  I’ve temporarily mislaid my copy of Chichester’s Alone over the Tasman Sea, but I can vaguely remember reading of him stowing his sextant box, not his box sextant.  Maybe I misread it.  Please point me in the correct direction.  I think the important thing is that the box and the conventional marine sextant are both ‘two mirror’ sextants making them relatively impervious to tilt in the direction of observation.  This is important because all aircraft are spirally unstable ‘hands off’,  and one might expect the Gipsy Moth, fitted with non-specific floats, and rebuilt after the damage at Lord Howe Island, to be particularly so. DaveP