Xil INTRODUCTION. 
of the world bears and lions and leopards and tigers ; 
but a love of science had no share in the motives for the 
gratification of which they were transmitted, and the chief 
curiosity manifested on such occasions by the people of 
Rome was to ascertain how speedily hundreds or thou- 
sands, as the case might happen, of these ferocious 
beasts would destroy each other when turned out half- 
famished into the public amphitheatre, or how long a 
band of African slaves, of condemned criminals, or of 
hired gladiators, would be able to maintain the unequal 
contest against them. The consul or emperor who 
exhibited at one time the greatest number of animals to 
be thus tortured before the eyes of equally brutal spec- 
tators was held in the highest esteem among a people 
who regarded themselves as civilized, and whose chief 
delight was in witnessing these wanton effusions of 
blood. It was only under the later Cesars that a few 
private individuals brought together in their vivaria a 
considerable number of rare and curious animals; and 
the Natural History of Pliny derives most of its zoolo- 
gical value from the opportunities which he had of 
consulting these collections. But the monstrous fables 
and the innumerable errors, which the most superficial 
examination would have taught him to correct, with 
which every page of this vast compilation absolutely 
teems, speak volumes with regard to the wretched state 
of natural science in the most splendid days of Roman 
greatness. 
From the unsuspecting credulity with which this text- 
book of the naturalists of the middle ages continued to 
be received, it is evident that the science remained 
stationary, if it did not actually retrograde, during the 
lapse of fourteen or fifteen centuries. The want of 
