section_path: High Middle Ages/Technology and the military
section_name: Technology and the military
paragraph_text: Technology and the military
  
  Technology developed primarily in minor innovations and the adoption of advanced technologies from Asia with Muslim mediation. Major technological advances included the first mechanical clocks and convex spectacles, and the manufacture of distilled spirits. In Europe, horizontal treadle looms were introduced in the 11th century; windmills were first built after 1100, and spinning wheels appeared c. 1200. Large scale construction projects advanced building technology, and increased demand for raw materials like timber, stone, and bricks. Shipbuilding improved with the use of the rib-and-plank method rather than the Roman system of mortise and tenon. Other improvements to ships included lateen sails and the stern-post rudder, both of which increased sailing speed. The astrolabe and compass allowed navigation at a great distance from shore.
  
  The development of a three-field rotation system for crops increased land use by over 30 per cent, with a consequent increase in production. The improvement of the plough allowed heavier soils to be farmed more efficiently. The spread of horse collars led to the use of draught horses, who required less pasture than oxen. Legumes such as peas, beans, and lentils were grown more widely, in addition to cereal crops.
  
  In military affairs, the use of specialised infantry increased. Along with the still-dominant heavy cavalry, armies often included mounted and infantry crossbowmen, sappers and engineers. Crossbow use increased, partly because of the increase in siege warfare. This led to the use of closed-face helmets, heavy body armour, and horse armour. In contrast, the Mongols remained lightly-armoured steppe horsemen even after they adopted Chinese military devices. The extensive use of spies for reconnoitering enemy land was a prominent factor in their successful military campaigns.