The art of dialling : performed geometrically, by scale and compasses, Two several ways. Arithmetically, by the canons of signs 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 discover'd. The third edition, enlarged. With a supplement, shewing how geometrically and mechanically to insert into all sorts of sun-dials, such circles of the Sun's course as gives the hour and length of the day, according to the account of several countries, &c. And to project and reflect hour-lines upon all sorts of superficies, plain or curved, without any regard had to their standing, either in respect of declination, or inclination. By William Leybourn, philomath.
by: Leybourn, William, 1626-1716
Published: (1690)
