182 EPOCHS IN THE HISTORY OP THE CONTEMPLATION 



observations to many genera of animals, by the fineness of 

 his distinctions, and the comprehensiveness of his physiolo* 

 gieal discoveries, " may be placed very near to Aristotle, 

 and in most respects even above him." It is Cuvier who 

 Las pronounced this judgment. ( 282 ) 



By the side -of Dioscorides and Galen shines a third -and 

 great name that of Ptolemy. I do not' cite him here as 

 the author of an astronomical system, or as a geographer; 

 but as an experimental physical philosopher, who measured 

 refractions, and, therefore, as the first founder of an important 

 part of optical science. His incontestable rights in this 

 respect were not recognised until very lately. ( 283 ) Important 

 as were the advances made in the department of organic life, 

 and in the general views of comparative zootomy, physical 

 Experiments on the passage of rays of light, at a period five 

 centuries anterior to that of the Arabians, must arrest our 

 attention yet more forcibly; they form, as it were, the first 

 step in a newly-opened course, in the vast career of mathe- 

 matical physics. 



The distinguished men whom we have named as shedding 

 scientific lustre on the period of the Roman empire, were all ol 

 Grecian origin; (the profound' arithmetical algebraist Die* 

 phantus, ( 284 ) who, however, was still without the use of 

 symbols, belonging to a later time.) In the two chief divi- 

 sions in respect to intellectual cultivation which the Eoman 

 empire presents to us, the palm was still with the Hellenes, 

 the older and more happily organised nation; but the gra- 

 dual decline of the Egyptian Alexandrian school was followed 

 by the dispersion of the still remaining, but weakened, 

 points of light in scientific knowledge and 'rational investi- 

 gation; and it was only at a later period that tiiey reap- 



