<P> The development of a three - field rotation system for planting crops increased the usage of land from one half in use each year under the old two - field system to two - thirds under the new system, with a consequent increase in production . The development of the heavy plough allowed heavier soils to be farmed more efficiently, aided by the spread of the horse collar, which led to the use of draught horses in place of oxen . Horses are faster than oxen and require less pasture, factors that aided the implementation of the three - field system . </P> <P> The construction of cathedrals and castles advanced building technology, leading to the development of large stone buildings . Ancillary structures included new town halls, houses, bridges, and tithe barns . Shipbuilding improved with the use of the rib and plank method rather than the old Roman system of mortise and tenon . Other improvements to ships included the use of lateen sails and the stern - post rudder, both of which increased the speed at which ships could be sailed . </P> <P> In military affairs, the use of infantry with specialised roles increased . Along with the still - dominant heavy cavalry, armies often included mounted and infantry crossbowmen, as well as sappers and engineers . Crossbows, which had been known in Late Antiquity, increased in use partly because of the increase in siege warfare in the 10th and 11th centuries . The increasing use of crossbows during the 12th and 13th centuries led to the use of closed - face helmets, heavy body armour, as well as horse armour . Gunpowder was known in Europe by the mid-13th century with a recorded use in European warfare by the English against the Scots in 1304, although it was merely used as an explosive and not as a weapon . Cannon were being used for sieges in the 1320s, and hand - held guns were in use by the 1360s . </P> <P> In the 10th century the establishment of churches and monasteries led to the development of stone architecture that elaborated vernacular Roman forms, from which the term "Romanesque" is derived . Where available, Roman brick and stone buildings were recycled for their materials . From the tentative beginnings known as the First Romanesque, the style flourished and spread across Europe in a remarkably homogeneous form . Just before 1000 there was a great wave of building stone churches all over Europe . Romanesque buildings have massive stone walls, openings topped by semi-circular arches, small windows, and, particularly in France, arched stone vaults . The large portal with coloured sculpture in high relief became a central feature of façades, especially in France, and the capitals of columns were often carved with narrative scenes of imaginative monsters and animals . According to art historian C.R. Dodwell, "virtually all the churches in the West were decorated with wall - paintings", of which few survive . Simultaneous with the development in church architecture, the distinctive European form of the castle was developed, and became crucial to politics and warfare . </P>

Each of the following is true about the dark ages in europe except which