On this point, it may be useful to mention the results of my own observation. At no period of my life am I conscious of having made greater progress than I have sometimes done while laboring in the summer; and almost incessantly too. It is true, I read but little; yet that little was well understood and thoroughly digested. Almost all the knowledge I possess of ancient history was obtained in this way, in one year. Of course, a particular knowledge could not be expected, under such circumstances; but the general impressions and leading facts which were imbibed, will be of very great value to me, as I trust, through life. And I am acquainted with one or two similar instances. It is true that mechanics and manufacturers, as well as men of most other occupations, find fewer leisure hours than most farmers. The latter class of people are certainly more favorably situated than any other. But it is also true that even the former, almost without exception, can command a small portion of their time every day, for the purposes of mental improvement, if they are determined on it. Few individuals can be found in the community, who have not as much leisure as I had during the summer I have mentioned. The great point is to have the necessary disposition to improve it; and a second point, of no small importance, is to have at hand, proper means of instruction. Of the latter I shall speak presently. The reason why laboring men make such rapid progress in knowledge, in proportion to the number of hours they devote to study, appears to me obvious. The mental appetite is keen, and they devour with a relish. What little they read and understand, is thought over, and perhaps conversed upon, during the long interval; and becomes truly the property of the reader. Whereas those who make study a business, never possess a healthy appetite for knowledge; they are always cloyed, nothing is well digested; and the result of their continued effort is either a superficial or a distorted view of a great many things, without a thorough or practical understanding of any. I do not propose, in a work of this kind, to recommend to young men what particular books on any subject they ought to study. First, because it is a matter of less importance than many others, and I cannot find room to treat of every thing.