period; but there were special compilations including very heterogeneous subjects, such as prayer, purification, fasting, pilgrimages, sales, the division of inheritances, marriage and so on: and under Mālikite influence these compilations were introduced into Spain.
In the days of the Caliphs Muslim Spain became one of the wealthiest and most thickly populated countries in Europe. Cordova expanded till it contained two hundred thousand houses, and, as we have seen, was greatly embellished in the reigns of 'Abd-ar-Raḥmān II and III, who erected the palace of Az-Zahrā, and under Almanzor who built the palace of Zāhira: another wonderful building was the Mosque, which was begun by 'Abd-ar-Raḥmān I. Cordova was the meeting point of travellers from all over the world, who came to admire the splendour in which the Caliphs lived.
This magnificence was due to the extraordinary growth of industry and commerce. In agriculture a distinct advance was made in the number of small holders, who also stood socially higher than under the Visigoths. The Arabs rapidly assimilated such knowledge of farming as the Spaniards possessed, and added to it the agricultural experience of other Asiatic peoples. The greatest writers on agriculture were Mozarabs; but the Arabs soon learned the lesson taught them, and successfully cultivated the vine on a large scale despite the prohibition of wine. The Muslims introduced the cultivation of rice, pomegranates, cane sugar, and other Oriental products. They started or completed a system of canals for the irrigation of gardens, especially in the provinces of Murcia, Valencia and Granada, and they were devoted to cattle breeding. It is noteworthy that the labourers used the Roman and not the Arab calendar.
Mining of gold, silver and other metals was pre-eminent among industries, the mines of Jaen, Bulche, Aroche, and Algarve being renowned, while the rubies of Béjar and Málaga were famous. The woollen and silk weaving in Cordova, Málaga and Almería was justly celebrated, and in Cordova alone there seem to have been thirteen thousand weavers. Paterna (Valencia) carried the ceramic art to great perfection, and Almería produced glass as well as many kinds of bronze and iron vessels. At Játiva the manufacture of writing-paper out of thread was introduced by the Arabs. Arms for defence and offence were made at Cordova and elsewhere, while Toledo was famous for its swords and armour. Cordova was the home of all kinds of leather industry, and thence was derived the trade term cordobanes (cordwainers). Ibn Firnās of Cordova, according to Al-Maḳḳarī, in the ninth century invented a method for manufacturing looking-glasses, various kinds of chronometers, and also a flying machine.
This industrial movement had far-reaching commercial results. Trade was mainly carried on by sea, and under 'Abd-ar-Raḥmān III the most important sources of revenue were the duties on imports and exports.
