That the skill of the sixteenth-century armourer surpassed that of the present-day craftsman is evident after careful examination of some of the triple-combed Burgonets and Morions of the middle of the century. They are often found forged in one piece with no sign of join or welding, and what is more remarkable still, there is but little difference in the thickness of the metal all over the piece. Now, when a smith hollows out a plate of metal into a bowl-like form, the edges are generally thicker than the inside of the bowl; but in many of these head-pieces the metal is almost of equal thickness all over, a _tour de force_ which few metal-workers to-day could imitate.[74] This thinning of the metal was utilized to a great extent in the different portions of the suit which were not exposed to attack. As will be found in the chapter on “Proof,” the back-plates were generally thinner than the breasts. In jousting-helms the top of the skull, which, from the position of the rider when jousting, was most exposed to the lance, was generally much thicker than the back of the helm, where there was no chance of attack. [Illustration: FIG. 29. Statue of S. George, Prague, 1375.] Again, the left side of both jousting and war harness is frequently thicker than the right, for it was here that the attack of both lance and sword was directed. Up to the middle of the fifteenth century the shield, hung on the left arm, was used as an extra protection for this the more vulnerable side of the man-at-arms, but it seriously interfered with the management of the horse. By the sixteenth century it was discarded and the armour itself made stronger on the left side both by increased thickness and also by reinforcing pieces such as the Grandgarde, the Passgarde, and the Manteau d’armes. [Illustration: FIG. 30. Sliding rivet showing (1) front, (2) side, (3) back.]