I do not mean by these remarks, that _playing on an instrument_ should be taught merely by listening to good music. Playing is a mechanical exercise, calling other faculties into activity, and cannot be acquired without practice. Besides, playing is not music, but only the means by which it is produced; and, so far as regards the music alone, the enjoyment is quite as great _whoever_ produces it, as if we ourselves did. Often, however, the mistake is committed of thinking that we are using the most effectual means to develope a taste for music, when we place the young person at an old piano to rattle out discordant sounds for several hours a day; and we are grieved and disappointed at the ultimate failure of an experiment which, in the very nature of things, could not possibly succeed. By assiduous practice on an instrument we exercise the _mechanical_ faculties, and may thus develope _their_ organs to an increased extent. But to produce the same effect on the faculty of Tune, we must stimulate it to sustained activity, by daily accustoming it to the hearing of exquisite music, and by guiding the judgment to the appreciation of beauties. We may then hope to promote increased action and growth in its organ. I believe that in regard to some of the other faculties we commit a similar mistake, and imagine that education fails to invigorate them and develope their organs, when, in fact, our endeavours have been wrongly directed, and could not be successful; but the present paper has run already to so great a length, that I must postpone any farther remarks on this part of the subject till another opportunity. Before taking leave, however, I would again enforce the absolute necessity of physiological knowledge for the successful guidance of teachers and parents. If the size of the cerebral organs admits of being increased by judicious exercise, and impaired or retarded by mismanagement, it obviously becomes an indispensable qualification for those who undertake their right direction to possess an accurate acquaintance with the functions and laws of the animal economy; and it is rather strange that we should have gone on to the present day without such an obvious truth having been universally perceived and acted upon.