Heart Motu Cordis" (1628) by the English physician William Harvey. Harvey's book completely describes the systemic circulation and the mechanical force of the heart, leading to an overhaul of the Galenic doctrines. Otto Frank (1865–1944) was a German physiologist; among his many published works are detailed studies of this important heart relationship. Ernest Starling (1866–1927) was an important English physiologist who also studied the heart. Although they worked largely independently, their combined efforts and similar conclusions have been recognized in the name "Frank–Starling mechanism". Although Purkinje fibers and the bundle of His were discovered as early as the 19th century, their
Doctor Who and the Daleks in the Seven Keys to Doomsday the universe with the help of their crab-like slaves, the Clawrantulars. The play was directed by Mick Hughes and written by Terrance Dicks, former script editor for the Doctor Who television series. Dicks would later use some of the plot elements in his Fourth Doctor story "The Brain of Morbius". The play was actually titled "Seven Keys to Doomsday" but the additional wording regarding Doctor Who and the Daleks came into common usage due to its prominence on promotional material. In December 1981, the Buxton Drama League staged a production at the Buxton Opera House in the United Kingdom, starring