After the capture of Jerusalem in 1099, almost the first operations of Godfrey de Bouillon were against the Syrian ports; but as he controlled too small a force to act alone, he made a treaty with Venice, by which, in consideration of two hundred ships, he promised to cede to her a third part of every town taken. Baldwin made a similar arrangement with the Genoese, and, as the coast was subdued, the Italian cities assumed their grants, and established their administrations. In the end the Venetians predominated at Tyre, the Genoese at Acre, and the Pisans at Antioch. Before the discovery of the Cape of Good Hope, the spices, drugs, brocades, carpets, porcelains, and gems of India and China, reached the Mediterranean mainly by two routes. One by way of the Persian Gulf to Bagdad, up the Euphrates to Rakka, and by land to Aleppo, whence they were conveyed by caravan either to Antioch or Damascus. Damascus, beside being the starting-place of caravans for Mecca and Egypt, and the emporium for the products of Persia, had important manufactures of its own. Its glass, porcelain, steel, and brocades were famous, and it was a chief market for furs, which were highly prized throughout the Middle Ages, when heating was not understood. The second route was by water. Indian merchants usually sold their cargoes at Aden, whence they were taken to a port in Upper Egypt, floated down the Nile to Cairo, and bought by Europeans at Damietta or Alexandria. The products of Egypt itself were valuable, and next to Constantinople, Cairo was the richest city west of the Indus. What Europe gave to the Orientals in return is not so well known; but, beside raw materials and slaves, her woollens were much esteemed. At all events, exchanges must have become more favourable to her, as is proved by the increased supply of the precious metals. Why the short period of expansion, which followed upon the re-establishment of the silver standard in the West, should have been succeeded by a sharp contraction is unknown, but the fact seems proved by the coinage. In the reign of Charlemagne a silver pound of 7680 grains was made the monetary unit, which was divided into 240 denarii, or pence.[127] For some time these pence were tolerably maintained, but as the empire of Charlemagne disintegrated, they deteriorated until, by the end of the twelfth century, those coined at Venice were but a quarter of their original weight and three parts alloy.[128] After Hattin a new expansion began, in which Venice took the lead. The battle was fought in 1187, and some years later, but probably before 1200, the grosso was struck, a piece of fine silver, of good weight, which thereafter was maintained at the standard. Half a century later gold appeared. Florence coined the florin in 1252, Venice the ducat in 1284, and between the two dates, Saint Louis issued his crowns.