The quadrant, sextant, and astrolabe wer the most prominent navigation tools of Columbus and the sailors who followed him during the Age of Discovery in the 16th and 17th centuries. When using the quadrant, sailors would locate the North Star with the viewfinder, and a weighted string would align itself with a degree marking telling you the angle between the star and the horizon. The sextant used an adjustable dial, as opposed to string, but ultimately, they all provided a working latitude for sailors.
Christopher Columbus used his knowledge of lunar cycles to trick natives on San Salvador into giving him food and shelter. They believed he could make the moon disappear forever and cause doom and destruction. It consisted of a sturdy wooden rod, tapered at both ends. Also called wrain stave. Was used together with ring bolts called wrung- or wrain-bolts , to force the planks closer to their shape and the ship's frame. Shipbuilding Tools. Adze: A shipwright's tool, similar to an axe , used for shaping and dressing wood.
Auger: A shipwright's tool for drilling holes in timbers. Axe: A shipwright's tool, the shipwright's axe came in a variety of shapes. Beetle: A shipbuilding tool.
Caulking Mallet: A shipbuilding tool. The Age of Exploration. Toggle navigation. Early Navigational Tools Determining latitude can be accomplished relatively easily using celestial navigation. Mariner's Compass. Nautical Charts. Astrolabe, Sextant, and Chip Log. Longitude and the Chronometer. Modern Navigation The twentieth century brought important advances to marine navigation, with radio beacons, radar, the gyroscopic compass, and the global positioning system GPS.
Gyroscopic Compass. Bibliography Rosenbach Company. User Contributions: 1. This web pae helped me alot with a school asignment. Thank you very very much! Cheers, Phoenix. Lyman Ward. Before the use of longitudinal reference using only latitude and the stars how did explorers attain any sense of accuracy in reaching the Americas. Comment about this article, ask questions, or add new information about this topic: Name:.
E-mail: Show my email publicly. Human Verification:. These areas of the world contained vast seas that were easily crossed using square sails. The Red Sea, and particularly the Gulf of Aqaba on the other hand were constantly exposed to contrary winds. In order to sail on these seas, sailors had to constantly battle winds that blew against them.
In this sort of setting the lateen sail was at its best. Secondly, the earliest evidence of the existence of lateens on the Mediterranean is in Greek Byzantine manuscripts of the late ninth century which show drawings of lateens.
Before this, in antiquity, only the square sail was found in this sea. This would lead us to suspect that the lateen came to the Mediterranean in the wake of the Arab expansion. Bibliotheque Nationale, MS, grec. They were quite unstable, and were never used to attempt to make headway against an adverse wind and thus were unable to make long journeys to cross oceans.
Then suddenly in the s, lateen sails burst on the scene, and ships developed into three masters with square sails complimented by lateen mizzens.
These ships were capable of making long ocean voyages and were used by Columbus, Diaz and Vasco da Gama. Lastly, it seems that during the Byzantine era, the forepart of the lateen sail was changed to a point, making it a complete triangle. The lateen eventually reached North European waters at the end of the Middle Ages, and there developed into every sort of fore-and aft rig.
Likewise, the lateen sail seems to have made its way from the Indian Ocean towards the seas of far south Asia. Since there are drawings from India, which demonstrate the use of the square sail there, and since the Chinese rigged their junks with square sails, it is safe to assume that the lateen sail was an Arab invention that most likely developed on the Red Sea.
The square sail was employed almost universally in the ancient world. It was only during the early Byzantine period in the eastern Mediterranean that any evidence emerges that triangular sails began to appear on the Mediterranean Sea. The square sail, though stable on heavy seas, is not very versatile to make much use of any headwinds. Square sails were still used until very recently on the sewn sambugs of Aden as well as lateen sails.
Many efforts must have been made to make the square sail better for sailing close to the wind, so it could utilize a head-wind. The simplest way was to set a square sail fore and aft, tilting it downwards at the fore end to make a balance lug illustrated here. From the lugsail it was an east step to shorten the luff fore part and heighten the sail aft to lengthen the leech, in order to catch more wind. The Arab lateen or more correctly, the settee sail is a very effective fore-and-aft rig.
It was developed in Arab waters well before the coming of Islam, and may have been the type of sailing ship that the Nabataeans would have used to sail on the difficult waters of the Red Sea. The final step was taken on the Mediterranean before AD, turning the Arab sail into a triangular sail. This type of sail was used on the Mediterranean for small boats for many years. The methods of sailing an ancient dhow must have been much like those today, since the rig was much the same.
In sailing with the wind the Arab lateen functions exactly as a square sail. When steering a course into the wind, the dhow would prefer to ear around, that is, to change tacks by going round stern to wind. Tacking involves bringing the bow around into the wind, and since Arab vessels were built with small rudders it was difficult or impossible to bring the bow across the wind, if the wind was strong.
Wearing around means losing way, but it is easier, to wear is to take the line of less resistance. When wearing, as when tacking, the yard must be transferred to the other side of the mast; but when wearing the wind aids this maneuver, whereas when tacking the wind tends to hinder it.
There was no reefing of sails in a strong wind, but the yard could be lowered, as today, and it is probably that a spare yard and sail of smaller size were carried, as in the vessels seen by Colomb in the nineteenth Century.
I demonstrate how the Nabataean people took to sailing ships. The speed at which they did this might be considered remarkable, if it were not for the fact that navigating in a featureless desert is very similar to navigating on a featureless ocean.
Therefore, before the Arabs became seamen they were knowledgeable in navigation skills. In the section below, I will demonstrate the basics of this navigation, whether it be used on the high seas, or in the depth of the Arabian desert.
However, not all Arab tribes knew how to navigate by the stars. Indeed, only a very few had this skill, as even today only the Slayb tribe are known as the trackers and guides in the desert. See: Where are the Nabataeans Today? Many early sailors sailed along the coast, always keeping land in site. In this way, they simply harbor-hoped along the coast.
One wonders what sea captain would have committed himself to the emptiness of the open sea without a knowledge of navigation by the stars. It would seem a small step however, for desert traveling Nabataean merchants to move on to being ocean traveling merchants, if they had the occasion to own ships and the need to transport goods by them.
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