The Speech of Monkeys

At other times I have approached the house from another direction, and come within a few feet of their cage, where I have stood for some time, in order to ascertain whether they were aware of my presence; and on a few occasions have slipped into the house with the crowd, and they did not detect my presence except by sight. It is evident, if they depended upon the sense of smell, that they would have discovered my presence when so near them, although they could not see me. But no matter what the condition of the weather, or how many people are present, the instant one of them sees me he spreads the news, and every inmate of the cage rushes to the window and begins to scream at the top of his voice. If their sense of smell was such as to enable them to detect my presence as a dog would, it is reasonable also that the monkey which possessed the most sensitive organs would have been the first to detect it in each case; whereas, sometimes one monkey, and sometimes another, made the discovery.