There is a passage of this period which describes Rupert as he appeared in Paris, "a straight and comely man, very dark-featured," probably owing to exposure in warm climates, "with jet black hair and a great passion for dress." He is often referred to in news-letters and diaries of the time under the sobriquet of the "Black Prince." "Our Black Prince Ruperte" records one, "has had a narrow escape from drowning in the Seine; but by the help of one of his blackamoors escaped." This was perhaps the period of the closest friendship between Charles and his Bohemian cousin; inasmuch as a decided coolness had already arisen on the part of the exiled monarch and his brother, the Duke of York. This coolness at length terminated in a quarrel, and a separation in the ensuing year at Bruges. Indeed, the Duke advised Rupert to have no further dealings with his royal brother, a proposition which the Prince wisely, and fortunately for himself, neglected to entertain, for had he acted otherwise, it is extremely doubtful if at the Restoration he would have been in a position to demand any favours at the monarch's hands. James, probably on this score, never afterwards professed much cordiality towards his kinsman, Rupert. [Sidenote: A patron of commerce.] In the years between 1656 and 1665, Rupert spent much of his time in cultivating science and the arts. There are a hundred evidences of his extraordinary ingenuity. A mere list of his devices and inventions, as printed at his decease in 1682, almost entitles him to be considered the Edison of his day, a day in which inventors were rare. Yet in the period before the outbreak of the Dutch war his activity was by no means limited to the laboratory which he had constructed for himself in Kings' Bench Walk, Temple, or to his study at Windsor. None could have exhibited greater versatility. In April, 1662, he was sworn a member of the Privy Council; he also became a member of the Tangier Commission; and in December of the same year he was unanimously elected a Fellow of the Royal Society. He already cut a prominent figure as a patron of commerce, being appointed a member of the Council of Trade, and taking an active part in the promotion of commerce with Africa as a member of the Royal African Company. With all his sympathies and activities, however, it is very clear that Rupert did not enjoy very great favour at Court. He was suspected of holding his royal cousin in not very high esteem, and of entertaining pronounced opinions on the subject of the royal prerogative; whatever the cause, his influence at Whitehall was not always fortunate. Seeing his councils neglected on several occasions, he kept aloof, and the courtiers, taking as they supposed their cue from their master, made light of his past achievements, finding in his surrender of the city of Bristol, a specially suitable subject for their derision.