Every one who has paid any attention to the subject must have observed the life, the energy, the enjoyment, which are observable in a class of children, while they are under the influence, and subjected to the discipline of the catechetical exercise. This will perhaps be still more remarkable, if ever they have had an opportunity of contrasting this lively scene with the death-like monotony of a school where the exercise is as yet unknown. Many can yet remember instances when it was first introduced into some of the Sabbath schools in Scotland, and the astonishment of the teachers at its instantaneous effects upon the mind and conduct of their children. The whole aspect of the school was changed; and the children, who had but a few minutes before been conspicuous only for their apathy, restlessness, or inattention, were instantly aroused to life, and energy, and delight. Similar effects in some children are still witnessed; but, happily for education, the first exhibition of it to a whole school is not so common. One striking proof of the novelty and extent of its effects upon the pupils, and of the vivid contrast it produced with that to which the teachers had at that time been accustomed, is afforded by the fact, that serious objections were sometimes made to its introduction, by well-meaning individuals, on account of its breaking in, as they said, upon the proper devotional solemnity of the children;--as if the apathy of languor and weariness was identical with reverence, and mental energy and joyous feelings were incompatible with the liveliest devotion. These opinions have now happily disappeared; and the catechetical exercise is not now, on that account, so frequently opposed. Christians now perceive, that by making these rough places smooth, and the crooked ways straight for the tottering feet of the lambs of the flock, they are following the best, as it is the appointed means, of "making ready a people prepared for the Lord." To the teacher, especially, it must be a matter of great practical importance, to perceive clearly the cause why this exercise is so fascinating to the young, as well as so beneficial in education. The cause, when we analyze all the circumstances, is simply this, that it resembles, in all its leading characteristics, those amusements and pastimes of which children are so fond. In other words, the prosecution of the catechetical exercise with the young, produces in reality the same effects as a game would do if played with their teacher. It brings into action, and it keeps in lively operation, all those mental elements, which, in ordinary cases, constitute their play; and the effects of course are nearly similar. We shall direct the reader's attention to this curious fact for a moment.