to sit on a fence and watch the birds; but if you really wish to learn you must mount a machine and become acquainted with its tricks by actual trial.'[2] This pronouncement, by the highest authority, may serve as an apology for some of those whose attempts were reckoned madness or quackery, and whose misfortunes, during many long centuries, are the only material available for the history of human flight. [Footnote 1: From the _History of Scotland_, by John Lesley, Bishop of Ross, written about 1570.] [Footnote 2: _Journal of the Western Society of Engineers_, vol. vi, No. 6, December 1901.] Two periods of modern European history are notable for a quickening of human interest in the problem of aerial navigation. They are the age of Louis XIV of France, and the age of the French Revolution. Both were times of great progress in science, and of illimitable hopes; but the earlier period, which in England witnessed the foundation of the Royal Society, was notable chiefly for advance in the physical and mathematical sciences; while the later period was more addicted to chemistry, and was the age of Lavoisier, Priestley, Cavendish, and Black. The former age, though it attained to nothing practical, made some progress in the theory of flight; the latter age invented the balloon. The Royal Society took its origin in the meetings in London, during the troublous times of the Civil War, of 'divers worthy persons inquisitive into natural philosophy'. One of these worthy persons was John Wilkins, mathematician, philosopher, and divine, who, being parliamentarian in his sympathies, was, on the expulsion of the Royalists from Oxford, made Warden of Wadham College in that University. At Wadham, in the Warden's lodgings, the 'Experimental philosophical Club', as Aubrey calls it, renewed its meetings. Sprat, the early historian of the Royal Society, explains that religion and politics were forbidden topics. 'To have been always tossing about some theological question would have been to make that their private diversion of which they had had more than enough in public; to have been musing on the Civil Wars would have made them melancholy; therefore Nature alone could entertain them.' After the Restoration a meeting was held at Gresham College in London, and a committee was appointed, with Wilkins as chairman, to draw up a scheme for the Royal Society. The King approved of the scheme submitted to him, and the society received its charter in 1662.