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. XVIII. How to draw the Reclining Declining Dial.

NOte, You have got the three principal Arches for the drawing the Hours.

• 1. The Arch of the Plane between the Horizon and the Meridian 54 deg. 44 min.
• 2. The Substile Distance from the Meridian of the Place OR 8 d. 17 m.
• 3. The Height of the Pole above the Plane or Stiles Height PR 14 d. 1 m.

How to draw the South declining West 45 deg. and reclining from the Zenith 45 d. is thus. First draw the Horizontal Line Fe, with your Compasses take off the Scale and Line of Chords the Radius 60 deg. and sweep the Circle FORPe; then take

[illustration] geometrical diagram

off the same Line of Chords 54 deg. 44 min. the Arch of the Plane between the Hori∣zon and the Meridian, and lay it from F on the Arch to O: Then take off your Line

of Chords 8 deg. 17 min. the Substile Distance, and lay it from O to R; then from the Center draw the Substile Line CG; then take of the Quadrant 90 deg. of the Line of Chords, and lay it both ways from R to M and N, and draw that obscure Line; then take off the Poles Height above the Plane or Stiles Height 14 deg. 1 min. from the Gnomon Line of the Scale, and lay it both ways from C to K; and then with your Compasses take off your Scale the whole Line of 6 Hours, and from K to∣ward G, and from I toward G, strike the two small Arches; then draw the Lines KG and IG; then extend the Compasses from G to the Meridian Line at L, and apply that Distance to your Scale and Hour-line, and you will find it to be 2 ho. 4 m. which is the Inclination of Meridians or Angle at P, as before: Then lay that Distance from L toward G, and take (as before directed in Chap. 17.) one Hour less, and lay it off in the same manner from G toward K, and from I toward G; and the like do with 3 ho. 4 min. until you have put all the 6 Hours on the Line from G to K, and from I to G. Then draw the Hour Lines according to your Plane, whether it be a Triangle, or Circle, or Square, or what shape soever; then lay off the Height of your Stile 14 deg. 1 min. from R to P, taken off the Line of Chords, and draw it from the Center, and cut it fit to your Plane in what shape you will, as you may see in the Figure, and your Dial is done. The opposite Face or Incliner to the Horizon is but to continue the Stile and Substile and Hour-lines through the Center, as you may see, and you have it. In like manner you may draw the South East Decliner 45 deg. and Reclining from the Zenith 45 deg. if you once draw on Paper this before, and the Hour-lines over the same, and the like the Substile, and the Stile to stand upon the Substile upright, as of the rest: And let the highest part of the Stile be towards the North Pole, pointing upwards; and where the Hour of 10 is in the South West Re∣cliner, on the back side put 2 a clock, and for 11 put 1, and for 1 put 11, and for 2 put 10, and so contrary all the rest. And if you observe your Work, you have the South West and the South East Recliners, and the North West and North East Incliners; or you may draw them by what was given in the first, in the same manner.