The author of "Calisto" also lost his credit with Rochester, so soon as he became generally popular; and shortly after the representation of that piece, its fickle patron seems to have recommended to the royal protection, a rival more formidable to Dryden than either Settle or "starch Johnny Crowne."[14] This was no other than Otway, whose "Don Carlos" appeared in 1676, and was hailed as one of the best heroic plays which had been written. The author avows in his preface the obligations he owed to Rochester, who had recommended him to the king and the duke, to whose favour he owed his good success, and on whose indulgence he reckoned as insuring that of his next attempt.[15] These effusions of gratitude did not, as Mr. Malone observes, withhold Rochester, shortly after, from lampooning Otway, with circumstances of gross insult, in the "Session of the Poets."[16] In the same preface, Otway, in very intelligible language, bade defiance to Dryden whom he charges with having spoken slightly of his play.[17] But although Dryden did not admire the general structure of Otway's poetry, he is said, even at this time, to have borne witness to his power of moving the passions; an acknowledgment which he long afterwards solemnly repeated. Thus Otway, like many others, mistook the character of a pretended friend, and did injustice to that of a liberal rival. Dryden and he indeed never appear to have been personal friends, even when they both wrote in the Tory interest. It was probably about this time that Otway challenged Settle, whose courage appears to have failed him upon the occasion.