222 THE HISTORY OF GEOLOGY 



I 



menced to arouse that serious attention which with 

 increasing earnestness has continued to be given to 

 them ever since. It is in two little books, one entitled 

 " Canis Carchariae Dissectum Caput," and the other " De 

 Solido intra Solidum Naturaliter Contento," published in 

 1669, that the germ of modern geology is to be found. 



They were written by the 

 famous Steno, the true foun- 

 der and father of our science. 

 Steno was by birth a Dane, 

 who occupied for a time the 

 Chair of Anatomy at Padua. 

 Dwelling thus not far from the 

 shores of the Adriatic, he was 

 able to make studies in marine 

 zoology, and of these the most 

 important was his dissection 

 of a shark's head. Steno paid 

 particular attention to its jaws 

 and teeth, which are well 

 worthy of study, as being pro- 

 bably the sharpest cutting 

 instruments naturally pro- 

 duced. But these put him in 

 mind of certain " glossopetrae " 

 which are dug out of the 

 ground in Malta, and on 

 making a careful comparison 



of the fossil with the recent teeth he convinced him- 

 self of their precise similarity (Fig. 80). But according 

 to Steno's logic, nothing but a shark could make 

 shark's teeth, and he consequently concluded that the 

 ancient glossopetrse had once belonged to the mouth of 

 a shark, and that the mouth opened into a shark's body 

 behind it. You cannot assert, he remarks, that Nature 



FIG. 80. Steno's Figure of the 

 Head of a Shark, showing 

 its teeth, with two "glosso- 

 petrse " represented below 

 for comparison. Taken from 

 his work " Canis Carcharise 

 Dissectum Caput," 1669. 



