Sir Walter Scott, according to Carlyle, was the only perfectly healthy literary man who ever lived,—­in fact, the one suitable text, he says, for a sermon on health.  You may wonder, Dolorosus, what Sir Walter Scott has to do with Angelina, except to supply her with novel-reading, and with passages for impassioned recitation, at the twilight hour, from the “Lady of the Lake.”  But that same Scott has left one remark on record which may yet save the lives and reasons of greater men than himself, more gifted women (if that were possible) than Angelina, if we can only accept it with the deference to which that same healthiness of his entitles it.  He gave it as his deliberate opinion, in conversation with Basil Hall, that five and a half hours form the limit of healthful mental labor for a mature person.  “This I reckon very good work for a man,” he said,—­adding, “I can very seldom reach six hours a day; and I reckon that what is written after five or six hours’ hard mental labor is not good for much.”  This he said in the fulness of his magnificent strength, and when he was producing, with astounding rapidity, those pages of delight over which every new generation still hangs enchanted.

He did not mean, of course, that this was the maximum of possible mental labor, but only of wise and desirable labor.  In later life, driven by terrible pecuniary involvements, he himself worked far more than this.  Southey, his contemporary, worked far more,—­writing, in 1814, “I cannot get through more than at present, unless I give up sleep, or the little exercise I take (walking a mile and back, after breakfast); and, that hour excepted, and my meals, (barely the meals, for I remain not one minute after them,) the pen or the book is always in my hand.”  Our own time and country afford a yet more astonishing instance.  Theodore Parker, to my certain knowledge, has often spent in his study from twelve to seventeen hours daily, for weeks together.  But the result in all these cases has sadly proved the supremacy of the laws which were defied; and the nobler the victim, the more tremendous the warning retribution.

Let us return, then, from the practice of Scott’s ruined days to the principles of his sound ones.  Supposing his estimate to be correct, and five and a half hours to be a reasonable limit for the day’s work of a mature brain, it is evident that even this must be altogether too much for an immature one.  “To suppose the youthful brain,” says the recent admirable report by Dr. Ray, of the Providence Insane Hospital, “to be capable of an amount of work which is considered an ample allowance to an adult brain is simply absurd, and the attempt to carry this fully into effect must necessarily be dangerous to the health and efficacy of the organ.”  It would be wrong, therefore, to deduct less than a half-hour from Scott’s estimate, for even the oldest pupils in our highest schools; leaving five hours as the limit of real mental effort for them, and reducing this, for all younger pupils, very much farther.