In addition to the respect they manifested for the customs of the country, Albert and Isabella showed the utmost interest in the restoration of every kind of social activity. Zealous for the welfare of Catholicism, they undertook to restore the religious life of the country. Three hundred churches and convents were rebuilt or founded. The religious orders of the Jesuits, the Carmelites, etc., found in the sovereigns hearty and generous protectors. The lost treasures of the churches had to be replaced, and the restoration of worship brought about the revival of the goldsmith’s art and of painting. The Flemish school of painting again became as famous as in the time of the Burgundian dukes. The head of this school was Peter Paul Rubens; and among his pupils he counted artists like Van Dyck, Teniers, and Jordaens. Public education was encouraged and many colleges and academies were opened for the teaching of Greek and Latin. The University of Louvain was accorded special protection. In 1607 Drusius, abbot of the abbey of Parc, near Louvain, and Van Craesbeke, councilor of Brabant, were appointed to inspect the University. Another delegate, the Nuncio Caraffa, was sent by the Pope. The system of “visitation,” as it was called, lasted, with interruptions, till 1617, when a complete scheme of regulations was enacted. The jurisdiction of the academic authorities, the privileges of the University, the interests of teaching and of the various colleges, the rights and duties of professors, the granting of degrees, the discipline and conduct of the students--everything was carefully dealt with. The visitation of 1617 established the authority of the University of Louvain and gave it a legal status. The excellent results of the new rules were immediately apparent. At this time seven or eight thousand students, among them Dutchmen, Frisians, Flemings, Germans, Frenchmen, Spaniards, and Italians, were in attendance at the University. The faculty of law became especially notable, and professors such as Peckius, Coursèle, Tulden, Perez, and Gudelin were regarded as eminent authorities. In letters the humanists Justus Lipsius and Erycius Puteanus, Valerius Andreas and Nicholas Vernuleus were famous. Albert and Isabella showed clearly their lively interest in the institution by attending one of the lectures of Justus Lipsius. Although artistic, literary, and scientific interests flourished during the reign of Albert and Isabella, the trade and industry of Belgium enjoyed no such revival. Antwerp was closed and had no access to the sea, as the Dutch blocked the Scheldt, and all commerce with the colonies of the New World was forbidden to the people of Belgium by Spain. Moreover, the peace and safety necessary to the development of trade were continually threatened by France in the south and by the United Provinces in the north.