170 Summer Studies of Birds and Books CHAP. 



forty-two years after his first arrival at Athens, he 

 was gathering more knowledge and adding it to his 

 book, or correcting, or perhaps striking out. It can 

 be quite plainly seen, from the text as we have it, 

 that additional notes were constantly put in, and 

 that the whole work was never finally completed. 

 We may suppose that the process of completion was 

 going on all the time that he spent chiefly on mental 

 and moral philosophy. Quite in the last years of his 

 life, long after he had been called back to Macedonia 

 to become tutor to the young Alexander the Great, and 

 had seen his pupil mount the throne and depart for 

 his expedition to the East, it is said that he was pro- 

 vided with money by the King for his researches, and 

 that the officers of the Macedonian army were ordered 

 to send him specimens, and to help him in every 

 possible way to carry on his work. 1 We cannot be 

 sure how far this is literally true, and we may be 

 pretty certain that another story, which tells how 

 Aristotle himself went with that famous army to 

 Asia Minor, Syria, and Egypt, is not to be credited ; 

 but it is quite probable that his old pupil, who loved 

 and reverenced him, at least until the last few 

 months of his life, should have used his unrivalled 

 opportunities to satisfy the old man's unlimited 

 curiosity. 



The work which thus took a lifetime, in all prob- 



1 Plin. N. H., viii. 44. Athenams, 398 e. 



