Development of the Lateen Sail

Overview

The lateen sail, developed during the first millennium, was introduced to medieval Europe where it revolutionized marine travel. Combined with the less-versatile square sail, the lateen sail was crucial to the development of navigable ships powered only by the wind. Their use in "foreand-aft" rigged ships helped to launch an era of seagoing commerce, exploration, and warfare that continued through the end of the Age of Sail.

Background

The first boats were crude, powered by a combination of water currents and human muscle power. They could travel downstream with ease, could traverse calm bodies of water with slightly more difficulty, and could travel against the current with great difficulty, if at all. Simple rafts could carry relatively large amounts of cargo, but only at the expense of maneuverability, while canoes (and canoe-like vessels) were maneuverable, but not very commodious. However, these simple craft were the only options for seaborne travel over many centuries, if not millennia.

The next advance was marrying a square sail to these craft. By doing this, a vessel could take advantage of the wind to help push it along its way, sparing the crew the effort of rowing. Unfortunately, a sail could only be used when the wind was blowing approximately in the desired direction of travel; the rest of the time it was more hindrance than help. So the utility of these first square sails, which could only take the wind from one direction, was limited due to the vagaries of the wind.

This does not mean that early craft were crude or clumsy. The ancient Greeks, Phoenicians, Romans, and other great civilizations conducted commerce, travel, and war with oared galleys that were both durable and nimble. However, these vessels were still dependent to some extent on muscle power and had only a limited ability to sail in any direction other than directly downwind.

The next breakthrough in sea travel came as early as the second century, with the invention of the lateen sail. Lateen sails were developed by the Arabs, then adopted in the eastern Mediterranean. Because they were used in the Mediterranean, northern sailors gave them the name "lateen" from "Latin." A lateen sail is a triangular piece of cloth. One side (two corners) is attached to a crossbar (called a yard) near the top of a mast, the third corner is fastened near the deck, and the mast or the crossbar pivots with some degree of freedom. The yard is often tilted at an angle to the ship's mast, so that the sail will often be in the form of a triangle with the point at the top of the mast. The lateen sail is called a "foreand-aft" sail because it is usually rigged such that the fabric of the sail itself runs along the length of the ship, or from the front end of the vessel towards the back (in nautical terms, from forward to aft, or fore and aft). This setup allows the sail to take the wind from directly astern (behind the ship) or from either side, and eventually was modified so that a ship could even sail into the wind. The lateen sail was soon combined with the older square sail, providing a good combination of steering and motive power. All in all, the lateen sail and its derivatives revolutionized going to sea.

Impact

The lateen sail had a tremendous impact on sailing, and on many areas affected by sailing, such as commerce, travel, exploration, and the military. Developments in these areas helped make some nations, including England and Spain, great powers.

The most obvious impact of the lateen sail was on the navigability and seaworthiness of deep-water ships. The older square sails (like those used by Viking ships) would only let a ship be blown before the wind because they were fixed to a yard rigidly mounted to a mast that was fixed to the deck. So long as the wind did not vary much in direction, the ship could raise the sail, but in variable winds or when navigating around complex shores, sailors could not count on the wind blowing from an appropriate direction.

In contrast, the lateen sail was mounted so that it ran along the length of the ship. This meant that even wind blowing from the side could be used to propel the ship forward. In fact, later ships were designed so they could sail somewhat into the wind using their rudder and rigging. While the lateen sail was not solely responsible for such maneuvering, it was certainly helpful.

While the added maneuverability of ships at sea was helpful, the impact of this maneuverability was significant in many other areas. No longer was a ship wholly at the mercy of the winds, and no longer was its range solely dependent on the ability of the crew to row. Instead, a ship's captain could shape his course from port to port. In addition, a ship could carry more stores and cargo because the ability of a crew to propel huge weights by sheer muscle power was no longer important. These two developments alone made seaborne commerce much more reliable and profitable, and helped to build the fortunes of maritime nations.

These same factors also affected naval warfare. The added power of the wind let ships carry more stores so they could stay at sea for longer periods of time. In addition, ships could be made larger, and heavy cannons could be mounted on them, turning the ship into a formidable weapon of war. These developments culminated in the huge fleets built by the Spanish, Dutch, French, and English at various times through the nineteenth century, and led also to profound revolutions in naval warfare.

Another area in which the benefits of the lateen sail were evident was in the ability of nations to begin the maritime exploration of the world. Although not much exploration took place until near the end of the fifteenth century, sailors in the few centuries leading up to that time learned how best to exploit the benefits of the new sailing rigs. In general, the same capabilities that made lateen-rigged vessels suitable for warfare and commerce also suited exploration. As before, the ability to navigate more predictably and reliably, combined with the greater cargo-carrying capacity of wind-powered ships, gave captains the confidence to strike out into the unknown and the ability to do so for longer periods of time. Until the fifteenth century, most sea travel took place either within sight of land or along very well-known and well-traveled sea lanes. This began to change with the introduction of more seaworthy vessels. For example, the ships Columbus sailed to the New World and those of Magellan had lateen sails.

Carrying people is little different from carrying any other sort of cargo. The same characteristics noted above also made it possible for ships to become troop transports, and they made ships capable of transporting large numbers of colonists or colonial administrators to distant lands. Both these developments were other ways of projecting a seafaring nation's power to the far reaches of the world, and helped to further solidify the dominant positions of the major powers for several centuries.

All the benefits of the lateen sail had a significant impact on the political power structure of Europe and the Mediterranean in the Middle Ages, an impact that increased with time. Probably the first use of lateen-rigged sailing vessels to project political power on a large scale was during the Crusades, when many of the European armies sailed on such ships to "liberate" the Holy Land. In large part, the military and commercial success of Venice was due to the use of lateen-rigged ships. These vessels carried Venetian goods throughout the Mediterranean and brought foreign trade goods back to Venice for sale to the rest of Europe. Venice was one of Europe's first commercial empires, and used some of this wealth to become one of the Mediterranean's most powerful states of that era.

Another marine innovation, probably introduced sometime in the twelfth century by pirates, was the stern rudder. By moving the ship's rudder from the ship's starboard side (the right-hand side as you face forward, also the side of the steering board) to the stern (the rear of the ship), the rudder could be fastened directly to the sternpost, making it stronger and less likely to be damaged in storm or battle. This not only made steering easier, but also allowed ships to increase in size by at least threefold. The larger ships had greater carrying weight for trade goods, which made voyages even more profitable, and for weaponry.

In later centuries, other nations used sea power as the basis for great national status. Portugal and Spain were first, sailing lateen-rigged ships on voyages of exploration and later of conquest. These same ships returned great amounts of riches to their mother countries, including trade goods from the Orient and riches plundered from the New World to Spain. Eventually, the English and Dutch became great powers based almost solely on their proficiency at sea. Both nations established colonial empires. The Dutch also built commercial power, and the English, military sea power. By this time, other innovations had increased the efficiency and seaworthiness of sailing ships further still.

The lateen sail was crucial for the development of ships that were maneuverable and reliable under sail power alone. These improvements made it possible for ships to increase in size, giving them the ability to carry cargo more profitably and more reliably. They also made ships more important as weapons of war. All these factors gave seafaring nations an advantage over their landlocked neighbors, and helped to shape the balance of power in the Mediterranean and in Northern Europe for centuries.

P. ANDREW KARAM