The compass was variously known in the Elizabethan age as the “sea-directorie,” the “nauticall box,” and the “sea-compasse.” Lightbody describes the bittacles as “little wooden pins for nailing the compass-box withal.” The first atlas was published in Dutch at Leyden in 1585 by Wagenaer. In this are to be found excellent coloured charts of the Narrow Seas. It is evident from these that there was a system of buoyage even in those days. There are barrel buoys, for instance, and basket beacons such as you can still find in use to-day in different parts of Holland. The sands on the port hand of the Swin Middle at the entrance to the Thames Estuary are shown marked by staff-and-triangle marks. This excellent atlas was soon translated into English, so that the elaborate sailing directions and the admirable little contours of the coast--crude but useful--could be placed at the service of English mariners. This English version was known as Wagenaer’s “Mariner’s Mirrour,” and there was also “The Sea Mirrour,” translated from the Dutch of William Johnson Blaeu by Richard Hynmers in 1625, which was another of the numerous nautical books of this time, containing instruction in practical navigation, sailing directions, charts, and contours. [Illustration: A CHART OF THE THAMES ESTUARY. (Dover to Orfordness.) This is taken from the first Atlas ever published, viz., in 1585.] [Illustration: “HOW YOU MAY AT ONE STATION MEASURE UPPON AN HEIGTH WITH A GEOMETRICALL SQUARE A LONGITUDE UPPON PLAINE.” This is from Lucar’s sixteenth-century treatise on gunnery, and illustrates the use of the “geometricall square” for finding the distance between the galley and the ship, viz. 300 yards. This instrument was made of metal or cypress, the quadrant being divided into 90 degrees. It was used for measuring “altitudes, latitudes and profundities,” and so very valuable for all gunnery work. ] The hourly or half-hourly glasses used on board were turned by the sentry, who struck the ship’s bell at every half-hour just as on shipboard to-day. The only means of keeping correct time in those days was by observing the heavenly bodies, and this gave time at ship. But frequently the navigators were many miles out in their longitude, since the latter is found by comparing the exact time at ship with the time by a chronometer showing the time at the prime meridian.