The mariners magazine, or, Sturmy's mathematical and practical arts containing the description and use of the scale of scales, it being a mathematical ruler, that resolves most mathematical conclusions, and likewise the making and use of the crostaff, quadrant, and the quadrat, nocturnals, and other most useful instruments for all artists and navigators : the art of navigation, resolved geometrically, instrumentally, and by calculation, and by that late excellent invention of logarithms, in the three principal kinds of sailing : with new tables of the longitude and latitude of the most eminent places ... : together with a discourse of the practick part of navigation ..., a new way of surveying land ..., the art of gauging all sorts of vessels ..., the art of dialling by a gnomical scale ... : whereunto is annexed, an abridgment of the penalties and forfeitures, by acts of parliaments appointed, relating to the customs and navigation : also a compendium of fortification, both geometrically and instrumentally / by Capt. Samuel Sturmy.

CHAP. VI. Of the kinds of Oblique Dials.

WHat an Oblique Dial is, and why it hath been so called, hath been shewed Chap. 2.

They be

• Regular.
• Irregular.

The Regular lie in some notable Circle of the Sphere; as first the Vertical Dial, whose Plane lieth in the Horizon, for which cause many call it the Horizontal Dial. Secondly, the South and North Horizontal Dials, whose Plane lieth in the East Azi∣muth, and is commonly called the South or North erect direct Dial. As for the East and West Dials, they belong to another place, as was said Chap. 5.

The Irregular are such as lie Oblique to the Horizon, as Reclining or Inclining Di∣als; or else lie Oblique to the Meridians, as Decliners; or else Oblique to both, as Recliners or Incliners declining, which are esteemed the hardest of all, because of their double irregularity.

The Declination of a Plane is the Azimuthal Distance of his Poles from the Meri∣dian of the place East or West.

The Reclination is the distance of his Poles from the Zenith and Nadir of your place.

Inclination is the neerest distance of the Poles of the Plane from your Horizon; and whatsoever the reclination of the upper face of a Plane is, the inclination of the lower face is the Complement thereof.