In writing, we have an action generally acquired earlier, done for the most part with great unconsciousness of detail, fairly well within our control to stop at any moment; though not so completely as would be imagined by those who have not made the experiment of trying to stop in the middle of a given character when writing at fit speed. Also, we can notice our formation of any individual character without our writing being materially hindered. Reading is usually acquired earlier still. We read with more unconsciousness of attention than we write. We find it more difficult to become conscious of any character without discomfiture, and we cannot arrest ourselves in the middle of a word, for example, and hardly before the end of a sentence; nevertheless it is on the whole well within our control. Walking is so early an acquisition that we cannot remember having acquired it. In running fast over average ground we find it very difficult to become conscious of each individual step, and should possibly find it more difficult still, if the inequalities and roughness of uncultured land had not perhaps caused the development of a power to create a second consciousness of our steps without hindrance to our running or walking. Pursuit and flight, whether in the chase or in war, must for many generations have played a much more prominent part in the lives of our ancestors than they do in our own. If the ground over which they had to travel had been generally as free from obstruction as our modern cultivated lands, it is possible that we might not find it as easy to notice our several steps as we do at present. Even as it is, if while we are running we would consider the action of our muscles, we come to a dead stop, and should probably fall if we tried to observe too suddenly; for we must stop to do this, and running, when we have once committed ourselves to it beyond a certain point, is not controllable to a step or two without loss of equilibrium.