The art of dialling [electronic resource] : performed geometrically, by scale and compasses: arithmetically, by the canons of sines and tangents: instrumentally, by a trigonal instrument, accommodated with lines for that purpose; the geometrical part whereof is performed by projecting of the sphere in plano, upon the plain it self, whereby not only the making, but the reason also of dials is discovered. The second edition diligently corrected and enlarged, with a second way of geometrical dialling, very easie, plain, and universal. By William Leybourn, philomath.