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Harvey, William (1578-1657).

Observationes et historiae omnes & singulae e Guilielmi Harvei libello De generatione animalium excerptae, & in accuratissimum ordinem redactae. Item Wilhelmi Langly De generatione animalium observationes quaedam. Accedunt Ovi faecundi singulis ab incubatione diebus factae inspectiones; ut et Observationum anatomico-med. decades quatuor; denique Cadavera balsamo condiendi modus.

Studio Justi Schraderi, M.D. Amstelodami, Typis Abrahami Wolfgang, 1674.

"Much of Harvey's work was concerned with eliminating the remaining vestiges of Aristotelian and Galenic doctrine from Fabrici's theory of oviparous generation, thereby shifting attention completely to the egg itself as a primary generative agent, quite distinct from parental semen and blood, on the one hand, and from the future chick, on the other. He could find no evidence that the seminal mass of the cock either enters into or even touches the eggs during their formation within the hen; furthermore, he found that for a time the hen can continue producing fertile eggs after all detectable traces of semen have vanished from her body. To Harvey this seemed to offer solid evidence that the contribution of the cock's semen to generation is indirect and incorporeal; it simply confers a certain fecundity on the hen and then plays no further role in the actual generation of the egg or the chick. Once endowed with this fecundity the hen can, entirely on her own, produce fertile eggs which will give rise to chicks resembling both herself and the cock. In trying to explain the transfer of this principle of fecundity from the semen to the hen, and from the hen to the egg, Harvey repeatedly cited the analogy of the spread of disease by contagion, in which mere exposure to a sick individual can engender within a second individual an internal principle which subsequently reproduces in him the same specific disease. The entire role of the parents in generation is to produce not a chick but a fertile egg, which subsequently gives rise to a chick through its own innate powers. For Harvey an egg was 'a certain corporeal substance having life in potency'; it was 'of such a kind that if all obstacles are removed it will develop into the form of an animal no less naturally than all heavy things tend downward, or light things move upward'. "An egg is the common primordium of all animals" (Dictionary of Scientific Biography).

"Born in Folkstone, Kent, he became the greatest name in English medicine through his discovery of the circulation of blood. This was published as Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus (An Anatomical Exercise on the Motion of the Heart and Blood in Animals) in 1628. He graduated from Caius College Cambridge and proceeded to Padua in order to study anatomy and physioloy under Hieronymus Fabricius ab Aquapendente. He obtained his diploma as a doctor of physick at Padua in 1602, and returned to England in the same year. On his return he was appointed physician at St Bartholomew's Hospital in 1609, and physician to James I in 1618, and later physician to Charles I (from 1640). His book on animal reproduction Exercitationes de Generatione Animalium, was published in 1651. Harvery refused to accept the presidency of Royal College of Physicians in 1654 and died three years later, and was buried at Hempstead Church" (Dictionary of the History of Medicine, p. 374).

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