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Ah, well I certainly didn't mean to troll. I had set up a problem where you have a fixed-angle sextant, because I am trying to figure out if it is possible to get latitide from the Sun with a Bris sextant. But, you also have a timepiece, and can take the angle as the Sun goes up, then down. So, mathematically (if not practically), longitude is straightforward (given the Equation of Time) with the Bris sextant. 

I do have 2 sextants, and have used them to shoot myself in without problem (although in the desert, not in a rocking sailboat - one is an A-12 and the other has a bubble level attachent), and obviously using a sextant would make shooting in the Sun at (or near) noon much easier. But I became intrigued by the mathematical challenge of using the Bris sextant to get latitude with those same 2 points, given the daily declination. It 'seems' like it should be doable, since you have 2 points that define an angle on a circle of known size. But I will admit to struggling a bit with the spherical trig.