6 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



having recognized the true nature of fossils, in despite of the popular 

 notions that they were relics of the Scriptural deluge, or sports of na- 

 ture generated within the solid rock tlirough the operation of some 

 occult force, or through the fermentation of a materia pinguis. 



Throughout the sixteenth and seventeenth centm-ies tlie nature and 

 origin of fossils remained a favorite topic of discussion. In the frequent 

 and often vexed disputes of this period are to be observed on the one 

 hand the influence of ecclesiastical prejudice, the Church claiming ability 

 to explain all things, and possessing means of proved efflcacy for com- 

 pelling the acceptauce of her views ; and on the other hand the per- 

 sistency of Aristotelian doctrines mingled with rank superstition. Such 

 was the infertile soil into which the method of experiment and observa- 

 tion endeavored to send its roots. A tender plant in the beginning, its 

 first green leaves withered, and during the long warfare between science 

 and theology its growth was retarded. Concerning the methods in vogue 

 during the period we are considering, it has been aptly remarked by 

 Lyell ^ that " the system of scholastic disputations encouraged in the 

 Universities of the middle ages had unfortunately trained men to habits 

 of indefinite argumentation, and they often preferred absurd and ex- 

 travagant propositions, because greater skill was required to maintain 

 them ; the end and object of these intellectual combats being victory 

 and not truth. No theory could be so far-fetched or fantastical as not 

 to attract some followers, provided it fell in with popular notions." 



In the midst of such conditions as these it is pleasing to note the 

 appearance of two men of remarkable insight, whose vision was in no 

 wise clouded by the prevailing atmosphere of superstition and dogmatism. 

 The first whom we have to consider is that versatile and brilliant genius, 

 Leonardo da Yinci (1452-1519), of whom Humboldt remarked that 

 "he was the first to start on the road towards the point where all the 

 impressions of our senses convey the idea of the Unity of Xature." His 

 clear exposition of the manner in which fossils have become preserved 

 in the rocks offers a refreshing contrast to the prevailing views of the 

 age, and although noticed by Humboldt,^ Lyell and others, his remarks 



1 Lyell, C, Principles of Geology, I. cli.ip. iii. London, 1834. 



2 Humboldt, A. von, Cosmos, II. chap. viii. Stuttgart, 1845. — Libri, G., Histoire 

 des sciences matheniatiques en Italie, III. Paris, 1840. — Lyell, C, Principles of 

 Geology, I. cliap. iii. London, 1830. — Raab, P., Leonardo da Vinci als Naturfor- 

 sclier, in Vircliow and Holtzendorff' s Snmmlung gemcinverstandl. Vortriige, ser. 

 15, p. 504. Berlin, 1880. — Ravaison-Mollien, C, Lcs manuscrits de Lc'onard de 

 Vinci. Manuscrits Fet / de la Bibliotheque de I'lnstitut. Paris, 1889. — Richter, 



