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 animals 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 language 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 communicate with his master: barking, four or five tones rich. The domestication of the dog is further so ancient a thing that it is pertinent to ask whether man himself had at that time any other language 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
