After a bit, the makers of armour discovered that much tedious labor in chain making might be spared, if one introduced a large plate of solid metal on the chest and back. This was in the thirteenth century. The elbows and knees were also treated in this way, and in the fourteenth century, the principle of armour had changed to a set of separate plates fastened together by links. This was the evolution from mail to plate armour. A description of Charlemagne as he appeared on the field of battle, in his armour, is given by the Monk of St. Gall, his biographer, and is dramatic. "Then could be seen the iron Charles, helmeted with an iron helmet, his iron breast and broad shoulders protected with an iron breast plate; an iron spear was raised on high in his left hand, his right always rested on his unconquered iron falchion.... His shield was all of iron, his charger was iron coloured and iron hearted.... The fields and open spaces were filled with iron; a people harder than iron paid universal homage to the hardness of iron. The horror of the dungeon seemed less than the bright gleam of iron. 'Oh, the iron! woe for the iron!' was the confused cry that rose from the citizens. The strong walls shook at the sight of iron: the resolution of young and old fell before the iron." By the end of the fourteenth and early fifteenth centuries, whole suits of armour were almost invariable, and then came the opportunity for the goldsmith, the damascener, and the niellist. Some of the leading artists, especially in Italy, were enlisted in designing and decorating what might be called the _armour-de-luxe_ of the warrior princes! The armour of horses was as ornate as that of the riders. The sword was always the most imposingly ornamented part of a knight's equipment, and underwent various modifications which are interesting to note. At first, it was the only weapon invariably at hand: it was enormously large, and two hands were necessary in wielding it. As the arquebuse came into use, the sword took a secondary position: it became lighter and smaller. And ever since 1510 it is a curious fact that the decorations of swords have been designed to be examined when the sword hangs with the point down; the earlier ornament was adapted to being seen at its best when the sword was held upright, as in action. Perhaps the later theory of decoration is more sensible, for it is certain that neither a warrior nor his opponent could have occasion to admire fine decoration at a time when the sword was drawn! That the arts should be employed to satisfy the eye in times of peace, sufficed the later wearers of ornamented swords.