Sect. I.] Zoblogij, 143 



view of the several kingdoms of nature, and to 

 state some leading facts concerning the progress 

 which has been made in each *. 



SECTION I. 



ZOOLOGY. 



At the beginning of the eighteenth century con- 

 siderable progress had been made in this branch 

 of Natural History, by the inquiries and discoveries 

 of Harvey, Redi, Malpighi, Willoughby, and Raj'. 

 These illustrious men discarded several erroneous 

 doctrines which had long been received, particu- 

 larly the doctrine of equivocal generation, and 

 threw much light on the principles of physiology. 

 Ray, being dissatisfied with Aristotle's classifica- 

 tion of animals, invented a new one, founded on 

 the structure of the heart. To this he was ])arti- 

 cularly led by the discoveries of Harvey, relating 

 to the circulation of the blood, which had been a 

 little before announced, and excited much atten- 

 tion in the philosophical V\'orld. From the time 

 of Ray till that of Linnocus f , Zoology was culti- 



* The coiitenls of tliis chapter have been principally collected 

 from Smith's Tracts on Natural History, and many other ^vork^. 

 on detached parts of tlie subject 3 some of whieli will be found 

 quoted, or referred to, in the following pages. For a knowled«;e 

 of some of the facts and names here detailed, 1 am indebted to 

 professor Barton, of Philadelphia, who, in a conversation on ilie 

 subject, furnished me with much valuable information, and with 

 profitable hints for directing my inquiries. 



t This '•' Prince of Naturalists" is so well known, that a for- 

 mal account of him in this place is altogetlicr unnecessary. He 



