The soldiers of Castile and Leon were then introduced into the citadels of the frontier; and the degenerate son of Mamun, who had already lost his capital, now saw himself about to be deprived of the remainder of his inheritance. Aware of the hopelessness of an attempt to reduce such a fortress as Toledo by means of mining or escalade, the Castilian sovereign resolved to try the tedious but more certain operation of famine. The walls were consequently invested; all avenues of supply were blockaded; and the beautiful valley of the Tagus was denuded of its orchards and its harvests. By a refinement of policy suggested by the peculiar relations existing between the crown of Castile and the Moorish governments of Andalusia, Alfonso adopted the profitable expedient of utilizing the Moslems as instruments of their own destruction. At regular intervals fiscal messengers were despatched to the capitals of the independent municipalities, and the sums thus collected defrayed the expenses of the siege of Toledo. So indispensable, indeed, were these contributions that without their aid no campaign of any length could, during the period under discussion, have been successfully prosecuted by the Christian monarchs of Spain. The revenues of states whose soil and climate were unfavorable to the operations of agriculture, and which were inhabited by a people constantly engaged in warfare, hardly sufficed to maintain the royal establishment, even in time of peace. The booty derived from predatory expeditions, although often of great value, was usually apportioned among the victorious soldiery in the field of battle, and was at once dissipated by the notorious improvidence of its recipients, while the uncertainty of its amount and the difficulty with which it was obtained rendered this source of supply unavailable for the pressing exigencies of the public service. Thus it may be seen how opportune was the regular income of Moorish gold which sustained for years the precarious fortunes of the Castilian monarchy, and by whose aid the vassals of the same suzerain were induced involuntarily to compass each other’s ruin. Familiarity with the use of such an invaluable expedient soon suggested various methods of improving its efficiency. The stipulated amount of the tribute was doubled. Extraordinary contributions were occasionally levied under the name of “gifts,” a species of extortion centuries afterwards adopted by the arbitrary sovereigns of civilized Europe as a convenient means of refilling a depleted treasury. In these financial transactions, the agency of Hebrews, whose heterodox opinions were not openly condemned so long as their unscrupulous schemes could be made to enure to the profit of the state, were exclusively employed. The arrogance of these emissaries, who exaggerated the importance of their trust, and, emboldened by their influence with the monarch, made no effort to disguise their power, was often intolerable. During the siege