In Palestine the Franks were surrounded by Saracenic buildings, and employed Saracenic masons, and the attention of Western architects seems no sooner to have been drawn to the possibilities of the ogive, than they saw in it the solution of those problems which had before defied them. An arch formed by two intersecting segments of a circle could be raised to any height from any base, and was perfectly adapted to vaulting the parallelograms formed by the columns of the nave. Therefore, contemporaneously with the building of the church of the Holy Sepulchre, the period of transition between the Romanesque and the Gothic opened in France. The two most important transition buildings were the abbey of Saint Denis and the cathedral of Noyon, and, while the Holy Sepulchre was dedicated in 1149, the abbey was completed in 1144, and the cathedral was begun almost immediately after.[108] Thenceforward the movement was rapid, and before the year 1200, Christian sacred architecture was culminating in those marvels of beauty, the cathedrals of Paris, of Bourges, of Chartres, and of Le Alans. Yet, though sacred architecture tells the story of the rise of the imagination as nothing else can, if it be true that centralization hinges on the preponderance of the attack in war, the surest way of measuring the advance toward civilization of rude peoples must be by military engineering. In the eleventh century, north of the Alps, this science was rudimentary, and nothing can be more impressive than to compare the mighty ramparts of Constantinople with the small square tower which William the Conqueror found ample for his needs in London. When the crusaders were first confronted with the Greek and Arabic works, they were helpless; nor were their difficulties altogether those of ignorance. Such fortifications were excessively costly, and a feudal State was poor because the central power had not the force to constrain individuals to pay taxes. The kingdom of Jerusalem was in chronic insolvency. The life of the Latin colony in Syria, therefore, hung on the development of some financial system which should make the fortification of Palestine possible, and such a system grew up through the operation of the imagination, though in an unusual manner. Fetish worship drew a very large annual contribution from the population in the shape of presents to propitiate the saints, and one of the effects of the enthusiasm for the crusades was to build up conventual societies in the Holy Land, which acted as standing armies. The most famous of the military orders were the Knights of the Temple and the Knights of Saint John. William of Tyre has left an interesting description of the way in which the Temple came to be organized:--