Portrait painting benefitted greatly from such commissions and from the general appreciation of art by bourgeois clients, who supported portraiture as well as still-life and landscapes painting. In addition, the first significant art and dealer markets flourished in Holland at that time. With plenty of demand, Rembrandt was able to experiment with unconventional composition and technique, such as chiaroscuro. He demonstrated these innovations, pioneered by Italian masters such as Caravaggio, most notably in his famous "Night Watch" (1642). "The Anatomy Lesson of Dr. Tulp" (1632) is another fine example of Rembrandt's mastery of the group painting, in which he bathes the corpse
History of anatomy research. Only certified anatomists were allowed to perform dissections, and sometimes then only yearly. These dissections were sponsored by the city councilors and often charged an admission fee, rather like a circus act for scholars. Many European cities, such as Amsterdam, London, Copenhagen, Padua, and Paris, all had Royal anatomists (or some such office) tied to local government. Indeed, Nicolaes Tulp was Mayor of Amsterdam for three terms. Though it was a risky business to perform dissections, and unpredictable depending on the availability of fresh bodies, "attending" dissections was legal. The supply of printed anatomy books from Italy and France