Rembrandt "Danaë", 1636), seeking to emulate the baroque style of Rubens. With the occasional help of assistants in Uylenburgh's workshop, he painted numerous portrait commissions both small ("Jacob de Gheyn III") and large ("Portrait of the Shipbuilder Jan Rijcksen and his Wife", 1633, "Anatomy Lesson of Dr. Nicolaes Tulp", 1632). By the late 1630s Rembrandt had produced a few paintings and many etchings of landscapes. Often these landscapes highlighted natural drama, featuring uprooted trees and ominous skies ("Cottages before a Stormy Sky", c. 1641; "The Three Trees", 1643). From 1640 his work became less exuberant and more sober in tone, possibly
Nicolaes Tulp of his books, Tulp became Mayor of Amsterdam in 1654, a position he held for four terms. His son Dirck married Anna Burgh, the daughter of Albert Burgh, another Mayor of Amsterdam who had, like Tulp, studied medicine in Leiden in 1614. In 1655 Tulp's daughter Margaretha married Jan Six, whom he helped become a Magistrate of family affairs in Amsterdam. Years later, Six would also become Mayor of Amsterdam. Tulp, impressed by his behaviour, invited Paulus Potter to come to Amsterdam, after a quarrel in the Hague. In 1673 Tulp was admitted to the Governing Committee of the Republic