The Anatomy Lesson of Dr. Deijman The Anatomy Lesson of Dr. Deijman The Anatomy Lesson of Dr. Deijman (alternative spelling Deyman) is a 1656, fragmentary painting by Rembrandt, now in Amsterdam Museum. It is a group portrait showing a brain dissection by Dr. Jan Deijman (161966). Much of the canvas was destroyed in a fire in 1723 and the painting was subsequently recut to its present dimensions, though a preparatory sketch shows the full group. The painting shows Dr. Deijman performing a brain dissection on the cadaver of an executed criminal, the Flemish tailor Joris "Black Jack" Fonteijn (1633/3456). Dr. Deijman's assistant, the surgeon Gijsbert Calkoen
Nicolaes Tulp the condition we know as migraine, the devastating effects of tobacco smoking on the lungs, and reveals an understanding of human psychology in a description of the placebo effect. Tulp also discovered the ileocecal valve at the junction of the large and small intestines, still known as Tulp's valve. While Tulp made observations of various diseases, treatment often continued in the age-old way. His description of the symptoms of Beriberi in a Dutch seaman, for example, went unnoticed until the cause (vitamin B1 deficiency) was recognized two hundred years later by Christiaan Eijkman. Partially as a result of the success