Re: Hemicyclium correction

Correction: I said that the declination lines would be circles around the cylinder's inside circumference. Actually, because the distance of the light-spot from the circumference-aperature varies, around the dial, the declination lines wouldn't be that simple. The drawing of the declination

Re: Hemicyclium correction

Of course, for the Cylinder Equatorial with circumference aperature, you could have declination-ilnes, which would be circles around the cylinder's circumference. Michael Ossipoff On Wed, Oct 18, 2017 at 10:23 PM, Brad Thayer wrote: > Michael, > > > > Thank you for

Re: Hemicyclium correction

Just one safety quibble: If you mount the spike sticking up, then it will be an eye-hazard, even with the ball on its end. That's a good reason to mount the spike horizontally, at the rim of the bowl. It could be mounted in a north-south groove at the south side of the bowl. Mounting the spike

Re: Hemicyclium correction

Dear Brad, I'm delighted that you enjoyued my "tutorial"... > However, its your step 19 I am > interested in. Ah yes. That's where I mention marking out equal hours. I thought you would be most interested in that step :-) You add... > And if I do tilt the hemispherium > so that the horizon