A 17th century illustration of the Hypothesis Tychonica from Hevelius' Selenographia, 1647 page 163, whereby the Sun, Moon, and
sphere of stars orbit the Earth, while the five known planets (Mercury, Venus, Mars, Jupiter, and Saturn) orbit the Sun.
It is conceptually a
geocentric model: the
Earth is at the centre of the universe, the
Moon and the stars revolve around the Earth, and the other five
planets revolve around the Sun.
At the same time, the motions of the planets are mathematically equivalent to the motions in Copernicus'
heliocentric system under a simple
coordinate transformation, so that, as long as no
force law is postulated to explain why the planets move as described, there is no mathematical reason to prefer either the Tychonic or the Copernican system. (Full article...)
An engraving by
Albrecht Dürer, from the title page of the
Masha'allah ibn Atharī's
astronomy treatise De scientia motus orbis (Latin version with engraving, 1504). As in many medieval illustrations, the
compass here is an icon of religion as well as science, in reference to God as the architect of creation.
Edward Drinker Cope (July 28, 1840 – April 12, 1897) was an American
ichthyologist. Born to a wealthy
Quaker family, Cope distinguished himself as a child prodigy interested in science; he published his first scientific paper at the age of 19. Though his father tried to raise Cope as a gentleman farmer, he eventually acquiesced to his son's scientific aspirations. Cope married his cousin and had one child; the family moved from
Haddonfield, New Jersey, although Cope would maintain a residence and museum in Philadelphia in his later years.
Cope had little formal scientific training, and he eschewed a teaching position for field work. He made regular trips to the
American West, prospecting in the 1870s and 1880s, often as a member of
United States Geological Survey teams. A personal feud between Cope and paleontologist
Othniel Charles Marsh led to a period of intense fossil-finding competition now known as the
Bone Wars. Cope's financial fortunes soured after failed mining ventures in the 1880s, forcing him to sell off much of his fossil collection. He experienced a resurgence in his career toward the end of his life before dying on April 12, 1897. (Full article...)
Image 24Image of
William Harvey's Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus. Harvey demonstrated that blood circulated around the body, rather than being created in the liver. (from Scientific Revolution)