INTRODUCTION. Xlll 



that ' a precise knowledge of what is already known is now 

 an indispensable requisite for carrying knowledge further,' ! 

 I set myself to the careful perusal note-taking the while 

 of the chief types of books which have been published 

 relating to the habits of animals a task which, along with 

 the arrangement of the resultant notanda, has occupied all 

 my leisure for several years. 



As a naturalist I have long been accustomed to the 

 patient and minute observation of facts, and to scientific 

 generalisation from facts. I have been trained to separate 

 fact on the one hand from fiction, and from inference based 

 upon observation, on the other. As regards the habits of 

 animals, I have had the same opportunities that all persons 

 possess in this country of observing mental phenomena in 

 domestic animals such as the dog, horse, cat, ox, fowl, and 

 in cage birds or other house pets. But I have also had the 

 opportunity which only foreign travel affords of observing, 

 if not studying, the manners of domestic and wild ani- 

 mals in many distant and different parts of the world in- 

 cluding parts of Europe between Iceland in the north, and 

 Spain and Italy in the south ; of Africa, including especially 

 Morocco and Egypt ; of Asia (to wit, Syria) ; of America, in- 

 cluding part of the United States and the Canadas; of Austra- 

 lasia, including New Zealand and New South Wales. The 

 animals observed included, for instance, the buffalo and the 

 camel, in addition to those above mentioned. I have, more- 

 over, visited sometimes repeatedly the principal zoologi- 

 cal gardens, or menageries, in the world such as those of 

 London, Paris (including the Jardin des Plantes and the 

 Jardin d'Acclimatation prior to the siege of Paris by the 

 Prussians in 1870-71), Berlin, Dresden, New York, Dublin, 

 Sydney, New South Wales, and that which formerly existed 

 in Edinburgh and have thus seen in the captive state large 

 numbers of wild animals, representing the /me natures of all 

 quarters of the globe. 



Regarding the whole subject of mind in animals 



1 In a posthumous letter published in the Athenaeum' of November 

 1873, p. 5G3. 



