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.

EXAMPLE II.

IN the height of 30 deg. he cometh a little before half an hour past nine of the clock to the East, and a little after half an hour past two of the Clock in the West, and so goeth in less than five hours and a half from the East through the South to the West; but from the West through the North, until again in the East, he go∣eth more than 18 hours. Thirdly, Being under the Line, and the Sun having no Declination, he ariseth in the morning right in the East, and so rising higher and higher, continueth East until that he goeth over our heads through the Zenith into the West; and so continueth West, still going down West, until he cometh again to the Horizon: and so according to a flat Compass he is the one half of the day East, and the other West, without coming upon any other Point. It is not so with this Aequi∣noctial Compass. The Sun and Moon go always a like time on every one Point of the Compass, to wit, from the East to the South 6 hours, from the South to the West 6 hours, from the West through the North to the East in twice 6 hours.

This Dial will serve for all Latitudes, if you put the end of the Wyre at D, to the height of the Pole or Latitude of the place as beforesaid; so the shadow of the other end at E will fall upon the Hours and true Points of the Compass, all the time the Sun is to the North of the Aequinoctial; but when the Sun is to South of the Aequi∣noctial, you must look for the Hours and Points of the Compass upon the under side of the Dial.