Sir Isaac Newton revolutionized natural philosophy by his discovery and demonstration of the law of gravitation, and Dr. William Harvey accomplished as great a change in physiological science by his discovery of the circulation of the blood. The most remarkable invention of the age was a rude steam engine, patented in 1698 by Captain Savery, and so far improved by Thomas Newcomen in 1712 that it was used for pumping water in coal mines for many years. Both were destined to be superseded by James Watt's engine, which belongs to a later period (1765). 522. Architecture. The Gothic style of the preceding periods was followed by the Italian, or classical, represented in the works of Inigo Jones and Sir Christopher Wren. It was a revival, in modified form, of the ancient Greek and Roman architecture. St. Paul's Cathedral, the grandest church ever built in England for Protestant worship, is the best example of this style. Many beautiful manor houses were built in the early part of this period, which, like the churches of the time, were often ornamented with the exquisite wood carving of Grinling Gibbons. There were no great artists in England in this age, though Charles I employed Rubens and other foreign painters to decorate the palace of Whitehall and Windsor Castle. 523. Education. The higher education of the period was confined almost wholly to the study of Latin and Greek. The discipline of all schools was extremely harsh. Nearly every lesson was emphasized by a liberal application of the rod, and the highest recommendation a teacher could have was that he was known as "a learned and lashing master." V. General Industry and Commerce 524. Manufactures. Woolen goods continued to be a chief article of manufacture. Silks were also produced by thousands of Huguenot weavers, who fled from France to England in order to escape the persecutions of Louis XIV. Coal was now extensively mined, and iron and pottery works were giving industrial importance to Birmingham and other growing towns in the Midlands. 525. Commerce. A permanent English colony was established in America in 1607, and by 1714 the number of such colonies had increased to twelve. During a great part of this period intense commercial rivalry existed between England and Holland, each of which was anxious to get the monopoly of the colonial import and export trade. Parliament passed stringent navigation laws, under Cromwell and later, to prevent the Dutch from competing with English merchants and shippers. The East India and South Sea companies were means of greatly extending English commercial enterprise, as was also the tobacco culture of Virginia. 526. Roads and Travel.