The mind grew because the body grew; more things were perceived, more things were handled, and being handled became familiar. But this came about chiefly because there was a hand to handle with; without the hand there would be no handling, and no method of holding and examining is comparable to the human hand. The tail of an opossum is a prehensile thing, but it is too far from his eyes; the elephant’s trunk is better, and it is probably to their trunks that the elephants owe their sagacity. It is here that the bee, in spite of her wings, has failed. She has a high civilisation, but it is one whose equilibrium appears to have been already attained; the appearance is a false one, for the bee changes, though more slowly than man can watch her; but the reason of the very gradual nature of the change is chiefly because the physical organisation of the insect changes, but slowly also. She is poorly off for hands, and has never fairly grasped the notion of tacking on other limbs to the limbs of her own body, and so being short lived to boot she remains from century to century to human eyes _in statu quo_. Her body never becomes machinate, whereas this new phase of organism which has been introduced with man into the mundane economy, has made him a very quicksand for the foundation of an unchanging civilisation; certain fundamental principles will always remain, but every century the change in man’s physical status, as compared with the elements around him, is greater and greater. He is a shifting basis on which no equilibrium of habit and civilisation can be established. Were it not for this constant change in our physical powers, which our mechanical limbs have brought about, man would have long since apparently attained his limit of possibility; he would be a creature of as much fixity as the ants and bees; he would still have advanced, but no faster than other animals advance. If there were a race of men without any mechanical appliances we should see this clearly. There are none, nor have there been, so far as we can tell, for millions and millions of years. The lowest Australian savage carries weapons for the fight or the chase, and has his cooking and drinking utensils at home; a race without these things would be completely _feræ naturæ_ and not men at all. We are unable to point to any example of a race absolutely devoid of extra-corporaneous limbs, but we can see among the Chinese that with the failure to invent new limbs a civilisation becomes as much fixed as that of the ants; and among savage tribes we observe that few implements involve a state of things scarcely human at all. Such tribes only advance _pari passu_ with the creatures upon which they feed.