Peter, surnamed II Tempesta and Pietro Muller or De Mulleribus, a distinguished painter, was the son of an artist of the same name, and was born at Haarlem in 1637. At an early age he was initiated in his art by his father, and is said to have been so fond of drawing, that he used to play truant from school, and to skulk by the sea-shore, sketching the ships in the distance, and the cattle that were grazing near him. His first models were the hunting pieces of Snyders; and his imitations, if continued, might in course of time have rivalled their originals. In his thirtieth year he was converted to Popery by a Carmelite monk, and shortly afterwards proceeded to Rome. There Molyn practised his art with great success. The Duke of Bracciano became his patron, and his fame rapidly increased. He was especially remarkable for the wild imaginative power with which he represented devoted ships tossing amid the confused turmoil of the elements. So striking, indeed, was his success in storm scenes, that he came to be generally known among the Italians by the name of "Tempesta." He also excelled in landscape-painting. His pictures of that description are marked by an imposing variety of scenery, consisting of woods, lakes, rocks, and romantic edifices, overhung by troubled skies, and relieved by lively and expressive figures. While Molyn was thus raising himself in the rank of his profession, he was also degrading himself in the scale of morality, and was fast becoming insensible to every virtuous emotion. At length, it is said, growing tired of his wife, an Italian lady, he left Rome on some pretence, and, after visiting Venice and Milan, settled in Genoa. From this city he was not long in despatching an accomplice to Rome with a letter to his wife charging her to come to him with the messenger. The lady, full of suspicion, at first refused, but on a second summons complied. She was murdered on the way by her companion; and her husband at the same time married a woman of Genoa, of whom he had become enamoured. Such suspicious circumstances led Molyn to be tried for murder, convicted, and condemned to perpetual imprisonment. The gloom of his dungeon, and the terrors of his guilty conscience, seem to have stimulated the peculiar powers of his imagination, for the tempests which he continued to paint were darker and more terrific than before. After Molyn had lain in prison for five years, according to some, or for sixteen years, according to others, he contrived to escape. Taking up his abode at Milan, he plied his pencil with greater success than ever, and increased both in influence and in profligacy. He lived most sumptuously, and kept a private menagerie to afford him facility for the study of animal-painting. At the same time he became so notorious a libertine that he received the additional surname of "Muller." Towards the close of his life the decaying faculties of Molyn failed to sustain him in his former style of living, and he lapsed into comparative poverty. He died of a fever in 1701. Many of his pictures may be seen among the collections in Milan and in its neighbourhood. (See Lanzi's History of Painting, and Stanley's Dutch and Flemish Painters.)