As the war grew more serious the purely Spanish troops were augmented by mercenaries, principally Swiss mountaineers. “Hardy warriors who fight on foot,” Pulgar describes them, “so resolved never to turn their back on the enemy that they wear defensive armour only in front, and are thus able to move with the greater ease.” The Swiss had won their laurels against Charles the Bold on the fields of Granson and Nanci; but even farther reaching than their vindication of national independence had been the triumph in their persons of infantry over cavalry; another blow struck at the old feudal ideas. In the war of Granada, it is still the cavalry who hold sway; but the presence of the Swiss foot-soldiers was not without its influence in the history of Spain, whose infantry, drilled and disciplined after their method by Gonsalvo de Ayora in the latter years of Ferdinand’s reign, was to become the admiration and fear of Europe. More immediate in its effects was the improvement of the artillery, a department of war that came under the Queen’s special supervision, and on which she expended her usual vivid interest and energy. A study of the almost barren results of the first two years of fighting had made it obvious that future campaigns must resolve themselves into a war of sieges, a war whose ultimate issue depended not so much on cavalry or infantry as on gunners and engineers. Isabel had already summoned from Germany and Flanders the men most gifted in this particular branch of military science, placing at their head Francisco Ramirez, a knight of Madrid, whose knowledge and experience was to win him the nickname “El Artillero.” [Illustration: DOUBLE BREECH-LOADING CANNON, IN BRONZE; USED IN SPAIN FROM THE END OF THE FIFTEENTH CENTURY FROM “SPANISH ARMS AND ARMOUR” REPRODUCED BY COURTESY OF THE AUTHOR, MR. A. F. CALVERT ] During the campaigns against the Moors in the reign of John II., Isabel’s father, the Christian army had been proud of its five “lombards” or heavy guns; but the growing importance of the artillery can be estimated, when we learn that in 1486, at the second siege of Loja, there were twenty lombards in action, while in two of the batteries placed before Malaga there were eleven heavy pieces, without counting the smaller ordnance.