heavily armed infantry could use their momentum in wedge formation to drive open small sections in the shield wall. This would break up the shield wall exposing the defenders to flank attacks. Western Europe Two complete descriptions of an infantry wedge are given by Saxo Grammaticus in his Gesta Danorum. In Book I, he describes a shallow wedge, with the front rank of two men then each thereafter doubled. In Book VII, he depicts a sharper pointed formation 10 men deep with the first rank being composed of 2 men, each rank composed of 2 more. Thus, each wedge was composed of 110 men, 10 deep, 2 men on its tip, and 20 on its base. According to the Vikings, the wedge formation, called by them svinfylking, cf. the Latin caput porcinum, was invented by Odin himself. A triangular or wedge formation was also used in the medieval period by the Flemish and Swiss infantry. Deep wedges of cavalry were used by German armies in the later Middle Ages. At the Battle of Pillenreuth in 1450, both the armies of Albrecht Achilles and Nuremberg fought in wedge formation. The Nuremberg cavalry was drawn up in a wedge led by 5 picked knights, then seven, then nine, then 11. The following twenty ranks held 250 ordinary men-at-arms, then a final rank of 14 picked men to hold the formation together. Sir Charles Oman refers to an unpublished manual of 1480 by Philip of Seldeneck which describes the formation, calling it the Spitz. He gives examples of various formations varying from 200 men to 1000. The formation of 1000 men places seven men in the first rank, with each rank increasing by two men back to the eighth rank with 21. The remaining men are in a column 20 men wide behind the point. The banner would be carried in the seventh rank. The use of the cavalry wedge in 13th Century Castile is described in the Siete Partidas, a law code compiled for king Alfonso X of Castile Byzantium Byzantine Emperor Nikephoros Phocas analyzes the wedge formation of the Byzantine Cataphracts in the third chapter of his Praecepta Militaria. There, he relates that the wedge must be formed by 354 cataphracts and 150 horse archers to a total number of 504 men. The row of the first line comprised 20 horsemen, the second 24, the third 28, down to the 12th