mosity of the pure republicans—of whom Sankey was a leader—being only too clear, Petty readily acquiesced in the Restoration. Charles II affected the society of scientific men, and took a special interest in shipbuilding. With his brother the Duke of York, he extended a willing welcome to Petty, whose acquaintance he had probably made as one of the members of a deputation from the Irish parliament, in which Petty sat for Enniscorthy. The king appears to have been charmed with his discourse, and protected him against the attacks of the extreme church and state party, which resented his latitudinarian opinions and viewed with dislike his connection with the Cromwell family, which Petty refused to abandon or disown. On the occasion of the first incorporation of the Royal Society (22 April 1662), of which he was one of the original members, Petty was knighted; and he received assurances of support from the Duke of Ormonde, who had probably not forgotten the efforts of Gookin and Petty on behalf of the ‘ancient protestants,’ of whom the duke was one, at the time of the transplantation. His cousin, John Petty, was at the same time made surveyor-general of Ireland.
Petty contributed several scientific papers, mainly relating to applied mechanics and practical inventions, to the ‘Philosophical Transactions’ of the Royal Society. He devised a new kind of land carriage; with Sir William Spragge he tried to fix an engine with propelling power in a ship; he invented ‘a wheel to ride upon;’ and constructed a double-keeled vessel which was to be able to cross the Irish Channel and defy wind and tide. This last scheme was his pet child, and he returned to it again and again. It is remarkable that the earlier trials of this class of ship—of which several were built—were more successful than the later. Petty maintained his confidence to the last in the possibility of building such a vessel; and in modern days the success of the Calais-Douvres in crossing the English Channel, though with the assistance of steam-power, has to a great extent justified his views. He sought to interest the Royal Society in very many other topics. ‘A Discourse [made by him] before the Royal Society … concerning the use of duplicate proportion … with a new hypothesis of springing or elastique motions,’ was published as a pamphlet in 1674. An ‘Apparatus to the History of the Common Practices of Dyeing,’ and ‘Of Making Cloth with Sheep's Wool,’ are titles of other communications made to the society (Spratt, Royal Society; Birch, Royal Society, i. 55–65).
The Acts of Settlement and Explanation (14, 15 Car. II, c. 2, 17, and 18 Car. III, c. 2, Irish Statutes), which decided or attempted to decide between those in actual possession of the greater part of the land of Ireland and those who at the Restoration claimed to be reinstated, secured Petty in a considerable portion of his estates. These estates, after the termination of the survey, he had greatly enlarged by prudent investments in land. The ‘Down Survey’ was also declared to be the only authentic record for reference in the case of disputed claims. During the whole of the remainder of his life, however, Petty was involved in a continual struggle with the farmers of the Irish revenue, who set up adverse claims to portions of his estates, and revived dormant claims for quit-rents. These pretensions he resisted with varying success, according as parties in England and Ireland ebbed and flowed. On one occasion in 1676 he involved himself in serious trouble by the freedom with which he spoke of the lord chancellor of England; on another he became the victim of the assaults of one Colonel Vernon, a professional bravo of the school of Blood. He was also challenged to fight a duel by Sir Alan Brodrick; but having the right, as the challenged party, to name place and weapon, he named a dark cellar and an axe, in order to place himself, being short-sighted, on a level with his antagonist. He thereby turned the challenge into ridicule, and the duel never took place. He received a firm support throughout the greater part of these transactions from the king and the Duke of Ormonde, though on at least two occasions he risked the loss of their favour by his firm determination to assert whatever he believed to be his just rights. It is much to the honour of the king and the duke, the latter of whom Petty describes as ‘the first gentleman of Europe’ (Life of Petty, p. 139, letter to Southwell, March 1667), and to whose eldest son, the Earl of Ossory, he was warmly attached, that the independent attitude of Petty never caused more than a temporary estrangement. At the time of the excitement incident to the ‘popish plot,’ Petty kept his head, notwithstanding the hatred of the system of the Roman church of which his writings show abundant evidence. He supported the moderate policy of the Duke of Ormonde on the ground that, even if the Roman catholic population wished to rebel, their means did not permit them to do so. His dislike also of the extreme protestant party led him to suspect the motives of those who exaggerated the danger. He was twice offered and refused a peerage. In the letter con-
