The Language of Animals
Those who have carefully observed the habits of animals have arrived at the conclusion, that most probably all species have some mode of communicating their ideas to each other. The insect tribes are the lowest in which this faculty has been detected. It does not appear to consist in the utterance of sounds, but chiefly in signs made through the sense of touch. One striking instance of a communication by ants was observed by Franklin. He had a pot of treacle in a cupboard to which the ants found access. He, then, to preserve his treacle, hung the pot by a string from the ceiling. It chanced that one ant had been left in the pot, and this animal he soon after observed leave it by the string, and passing along the ceiling towards its nest. In less than half an hour, a great company of ants sailed out of their hole, climbed along the ceiling and descending by the string, resumed their feast at the treacle. As one set was satisfied, it left the treacle to give place to another; and there was a constant passing up and down the string until the whole of it was eaten up. In this case there could not, be the least doubt that the single ant had given information of a means having been left by which they could again approach the pot, and this information led to the new attack which the colony made upon it.
In the mammalia, existence of some means of communication can be proved, by almost daily observation. A bull, seeing a cow straying behind the rest of the herd, will go towards it, and call something, which causes the cow to rejoin her companions. Again, it is related that an old mare being relieved, in consideration of age and infirmity, from heavy labour, was turned out in company with a cow and four or five heifers into a small field at a distance from her former companions. The grass in this enclosure was not very plentiful, and the adjoining pasture being full of luxuriant vegetation, and divided by a broken-down fence, they frequently took the liberty of trespassing upon the neighbouring property. This occurred so often that a watch was set upon their actions. The mare, tired of staying so long in the same field, made a circuit of it, with a view of escaping from her confinement; and having discovered a place suited for her exit, she returned to her horned companions, who were chewing the cud at a little distance, and having approached the cow, she gently struck her on the shoulder, first with her hoof and then with her head. The cow rose up and the two advanced towards the gap, and having jointly reconnoitered it, returned to the rest; and then, the old mare leading the way, the whole company leaped over in succession after her.
These examples make it clear that some means of communication exist. This language among the insect tribes chiefly consists of signs by touch. Of what nature is the language of the mammalia? These can convey expressions of hunger, impatience, and some other feelings, by their looks and attitudes; but, judging from Cattle which have been observed to take joint action after holding their heads together, they have evidently in addition another mode of communicating their ideas in which neither sounds nor signs are used. Of what nature this silent speech is, it is impossible to say.