The English globe being a stabil and immobil one, performing what the ordinary globes do, and much more / invented and described by the Right Honorable, the Earl of Castlemaine ; and now publish't by Joseph Moxon ...

OPERATION XXVI▪ How to make a Dial on any Plane whose stile shall be an Arrow fixt casually on it.

EXamine what the Plane is, and having found it to be, sup∣pose,* 1.1 a Vertical one Declining 40 Degrees East-ward, de∣scribe by your* 1.2 former Rules: such a Dial on Paper with the Pa∣per stile F x, M. (as in Scheme 31.) exactly set, and mounted; then draw on the Plane an Horizontal Line H h, and place on it your said Paper draught so, that the 12 a clock Line FP may fall at right Angles on the said Horizontal line. Lastly, move your Draught along it, till some part of F x or Indicating side of the stile, (suppose the Point A) just touches the Top or most promi∣nent Part of the Arrow, and fixing there the said Draught, if you draw fair Lines on your Plane under those on the Paper, the said Arrow will always show you the Hour with its Top.

The Reason is plain: for you see by the said Top's just touch∣ing* 1.3 the Edge, or Indicating side of the Paper-stile, it has the ef∣fect of the Top of AB, I mean the Top of a Perpendicular fall∣ing from the said side on the Sub-stile, so that X the Top of XM (both in the present Scheme and also in Scheme.* 1.4 18. or Example of a Declining Plane) has this Effect also. Now since the Top of AB or XM or of any other Perpendicular, that falls

from the Indicating side XF on the substile FM will perform the Office of the stile (as we show'd you at large in Demonstra∣tion of the * 1.5 first Horizontal Dial or first Example,) it must necessarily follow, that A the Arrow's Top do's the like.

Notes

• * 1.1

  The Constru∣ction:
• * 1.2

  pag. 89.
• * 1.3

  The Demon∣stration.
• * 1.4

  pag. 94.
• * 1.5

  pag. 75.