For the rest the Spaniards originated a system which, though it now seems obvious enough, was in those days a new thing. It consisted simply in the maintenance of a nucleus, or as we should now call it a depôt, of trained men sufficiently numerous to teach recruits their duty. All recruits were trained in the garrisons at home, and from thence passed into the ranks of the regiment wherein they were needed; and every draft so disposed of was immediately replaced by an equal number of new recruits. When it is remembered that, according to the ideas of the time, seven thousand trained infantry and three thousand cavalry were judged sufficient to leaven an army of fifty thousand men, the strength which her system of recruiting gave to Spain is not easily exaggerated. The trained regiments of Spanish infantry were but four, and their united strength did not exceed seven thousand men, but their ranks were always full. The number of companies into which they were distributed was uncertain, and the strength of the companies themselves varied from one hundred and fifty to three hundred men, a curious defect in the most perfect organisation of the time. Lastly, the Spanish regiments were known by the name of tercios,[74] a term with which the reader must not quarrel, as he will encounter it on the battlefield of Naseby. [Sidenote: 1475.] [Sidenote: 1567.] Not less remarkable than their forwardness in organisation and discipline was the ready quickness of the Spaniard in the improvement of fire-arms. The primitive hand-gun, as I have already said, differed little except in size from the smaller cannon of the time. It consisted simply of a barrel with a vent at the top, and though indeed attached to a wooden stock had no lock of any description. Hand-guns were often made so short that they could be held even by a mounted man with one hand and fired with the other. Match-cord or tinder for purposes of firing the charge by the vent was already in full use. The next step was to increase the length of the barrel and support it on a forked rest, a plan introduced by the Spaniards at Charles the Fifth's invasion of the Milanese in 1521. Ten years later a vast stride was made by the substitution of a pan at the side of the barrel for a vent at the top, and by the addition of a grip to the stock to hold the match-cord, which was brought in contact with the pan by pressing a trigger. In a word, the barrel was fitted with a lock. An extremely ingenious Italian in the French service, Filippo Strozzi, then took the improvement of fire-arms in hand, copying however, as always, from the Spanish model. The bore of the harquebus (for the primitive German _hakenbuchse_ had by this time found its permanent corrupted form) was by him enlarged to bear a heavier charge and carry a larger bullet; and so perfect was the workmanship of the Milanese gunsmiths whom he employed that he succeeded in killing a man at four hundred and a horse at five hundred paces. The stock