30 MEMOIRS OF 



lively speaking, in a much less advanced state. On look- 

 ing back to the history of this science from the beginning, 

 we shall see three great names the possessors of which 

 caused the most important revolutions, who gave fresh im- 

 pulse towards its perfection, and who have been the oracles 

 of the civilized world. To be able to mark the differences 

 of one being from another is the foundation of this science ; 

 the great number of these beings necessitates classification, 

 in order to assist the memory, and facilitate a perfect com- 

 prehension of their nature and properties, and the part 

 they perform in creation. To Aristotle belongs the honour 

 of the first epoch, by having invented the true method, 

 that alone which can be permanent, as it is founded upon 

 organization, and is the result of personal observation. 

 The writers after him, till the northern barbarians for a 

 time buried all letters in obscurity, contented themselves 

 with copying what he had done from one work into an- 

 other, and by no means followed his example of seeing 

 and judging for themselves. During the middle ages, 

 now and then an enlightened monk, for a moment, threw 

 a glimmering light over some branch of animated nature, 

 and the first revival of learning presents us with many 

 able efforts in this department of science. At length Lin- 

 naeus appeared, and formed the second era. He assembled 

 all known living beings together, and classed them accord- 

 ing to the mass which he brought before him, selecting 

 one or two individual characters as the foundation of his 

 clear and simple system, and by this, and by his ingeni- 

 ous binary nomenclature, not only accomplished the great 

 object of natural history, which is to make us acquainted 

 with the beings themselves, but by thus collecting them 

 together, greatly contributed to our knowledge of their 

 affinities. It was easy to be seen, however, that in pro- 

 portion as our knowledge of nature increased, this artificial 

 classification would scatter so many groups that were in- 

 tended to remain united among themselves, that it would 

 be found insufficient for the enlarged scale which the dis- 

 coveries of every year presented to us. The Systema Na- 

 turae then of Linnaeus became a mere sketch of what was 

 to be done afterwards ; even more recent naturalists touch- 

 ed with a timid hand upon the natural grouping of the 



