but, if we would have successful soul-oculists, not merely that organ, but the general anatomy and constitution of the intellectual frame must be studied; for the powers of that eye are affected by the general state of the system.  My meaning is, that piety and religion will be the best understood by him who takes the most comprehensive view of the human mind, and that, for the most part, they will strengthen with the general strength of the mind, and that this is best promoted by a due mixture of direct and indirect nourishment and discipline.  For example, Paradise Lost, and Robinson Crusoe, might be as serviceable as Law’s Serious Call, or Melmoth’s Great Importance of a Religious Life; at least, if the books be all good, they would mutually assist each other.  In what I have said, though following my own thoughts merely as called forth by your Appendix, is implied an answer to your request that I would give you ‘half an idea upon education as a national object.’  I have only kept upon the surface of the question, but you must have deduced, that I deem any plan of national education in a country like ours most difficult to apply to practice.  In Switzerland, or Sweden, or Norway, or France, or Spain, or anywhere but Great Britain, it would be comparatively easy.  Heaven and hell are scarcely more different from each other than Sheffield and Manchester, &c., differ from the plains and valleys of Surrey, Essex, Cumberland, or Westmoreland.  We have mighty cities, and towns of all sizes, with villages and cottages scattered everywhere.  We are mariners, miners, manufacturers in tens of thousands, traders, husbandmen, everything.  What form of discipline, what books or doctrines—­I will not say would equally suit all these—­but which, if happily fitted for one, would not perhaps be an absolute nuisance in another?  You will, also, have deduced that nothing romantic can be said with truth of the influence of education upon the district in which I live.  We have, thank heaven, free schools, or schools with some endowment, almost everywhere; and almost every one can read.  But not because we have free or endowed schools, but because our land is, far more than elsewhere, tilled by men who are the owners of it; and as the population is not over crowded, and the vices which are quickened and cherished in a crowded population do not therefore prevail, parents have more ability and inclination to send their children to school; much more than in manufacturing districts, and also, though in a less degree, more than in agricultural ones where the tillers are not proprietors.  If in Scotland the children are sent to school, where the parents have not the advantage I have been speaking of, it is chiefly because their labour can be turned to no account at home.  Send among them manufacturers, or farmers on a large scale, and you may indeed substitute Sunday-schools or other modes of instructing them; but the ordinary parish schools will be neglected.