EDUCATION IN THE ANIMAL KINGDOM. 533 



men, too, have recourse to the tactile language. I once knew an 

 elderly woman, deaf and blind, who could be conversed with in 

 silence by touching one finger or the other, or this or that joint, to 

 designate the different letters of the alphabet and even certain words 

 and punctuation points. Travelers in the Orient, especially Chardin, 

 have described a similar language as used by Persians and Arabs in 

 making their bargains, so as to evade the impertinent curiosity of 

 the crowd. 



Singing birds have the advantage in language over all other ani- 

 mals except man. Among them, Syme has distinguished six classes 

 of expressions: the call of the male in spring, the noisy sounds of 

 mistrust, the warning uttered when a bird of prey is seen, the call of 

 parents and the response of the young, the warbling or cooing of 

 love, and cries of fear or of alarm for the nest. It is not necessary 

 to suppose that this language of birds is inborn. It results,. on the 

 other hand, from acquisitions made during the life of the species 

 which are not completely transmitted by heredity. Young birds 

 have to go through a process of teaching to sing well. Their first 

 efforts may be compared with the prattle of children. Singing lan- 

 guage is the property only of particular species of birds. The crow 

 does not sing like the nightingale, although it has a similar larynx. 

 Young birds learn to sing by spontaneous imitation and practice, and 

 of course take the song of their parents; but in aviaries they often 

 copy the songs of other species, just as our children learn foreign 

 languages by hearing them spoken. It therefore seems clear that the 

 artistic talent of singing birds has been slowly acquired. The dog 

 did not learn to bark till he fell into the society of man. He does 

 not, indeed, imitate human language; but, desiring to express novel 

 feelings, he has created a language of his own in order to communi- 

 cate with his master: barking, four or five tones rich. The do- 

 mestication of the dog is further so ancient a thing that it is per- 

 tinent to ask whether man himself had at that time any other lan- 

 guage at his disposal than modulated cries. But although they do 

 not speak as we do, dogs very well understand some words and 

 phrases, and by training this intelligent comprehension of language 

 can be greatly enriched. Their mental condition may be compared 

 in this respect to that of our children between the ages of ten and 

 twelve months, who understand a considerable number of words, 

 but are not yet able to articulate them. So, likewise, an adult man 

 going into a foreign country learns to understand the words of the 

 new language before he begins to speak them. 



Our dogs understand, too, the languages of animals of different 

 species with which they are associated. The dogs Houzeau kept in 

 Texas to guard his poultry yards responded to the cries of the fowl 



