Nine geometricall exercises, for young sea-men and others that are studious in mathematicall practices: containing IX particular treatises, whose contents follow in the next pages. All which exercises are geometrically performed, by a line of chords and equal parts, by waies not usually known or practised. Unto which the analogies or proportions are added, whereby they may be applied to the chiliads of logarithms, and canons of artificiall sines and tangents. By William Leybourn, philomath.

Arts and Sciences MATHEMATICALL Professed and Taught by the Authour.

• ...Arithmetick,
  • In Whole Numbers, and Fractions.
  • In Decimals, and by Logarithms.
  • Instrumentally, by Decimal Scales, Napiers Bones: and to extract the Square and Cube Roots by Inspection.
• ...Geometrie:
  • The Principles thereof with the
    • Practice, and
    • Demonstration.
• ...Astronomie:
  • The Description of the Circles of the Sphere.
  • The Use of the Globes,
    • Celestiall, and
    • Terrestriall.
  • To project the Sphere in Plane upon any Circle,
    • Right, or
    • Oblique.

And upon these Foundations the following Superstructures.

• The Use of Geometricall Instruments, in the Practice of
  • Longimetria, or the Mensuration of
    • Heights, as of Trees, Towers, &c.
    • Depths, as of Mines, Wells, Des∣cents, &c.
    • Distances, as of Churches, Towers, &c.
  • Planometria, or the Mensuration of
    • Board,
    • Glass,
    • Pavement,
    • Tiling, &c.
    Or any other Superficies.
  • Stereometria, or the Mensuration of
    • Timber, growing or squared.
    • Stone, regular or irregular.
    • Cask, commonly called Gageing.
  • Geodaesia, or the Measuring of Land divers waies, and by severall Instruments; to draw the Plot of a whole Mannor or Lordship; to cast up the Content thereof; and to beautifie the same with all necessary Ornaments thereunto belonging.
• ...Trigonometria:
  • Or, the Mensuration of Triangles, both
    • Plain, and
    • Sphericall.
  • The Application thereof, in the soluti∣on of Problems in
    • Geometry.
    • Astronomie.
    • Geographie.
    • Navigation.
    • Fortification.
    • Dialling, &c.
• ...Navigation:
  • The Principles thereof, and the manner of Sailing by
    • The Plain Sea-Chart.
    • Mercator's Chart.
    • The Arch of a great Circle.
• Horologiographia Or Dialling:
  • Arithmetically, by the Tables of
    • Sines.
    • Tangents.
    • Logarithms.
  • Geometrically, by
    • Scale, and
    • Compasses.
  • Instrumentally, by the Sector, Quadrants, Scales, and other Instru∣ments accommodated with Lines for that purpose.

You may hear of him at Mr. Hayes's at the Cross-daggers in Moor-fields.

ADVERTISEMENT.

AND here I thought good to give notice, That if any Gentlemen studious in the Mathematicks have or shall have occasion for Instruments thereunto belonging, or Books to shew the Ʋse of them, they may be furnished with all sorts usefull both for Sea or Land, either in Silver, Brass or Wood, by Walter Hayes, at the Cross-daggers in Moor-fields, next door to the Pope's-head Tavern; where they may have all sorts of Maps, Globes, Sea-plats, Carpenters Rules, Post and Pocket-Dials for any Latitude.