women of the artisan class as to those socially above them--then indeed I should cry, God help us and those that are to come after us! Owing to causes which are obvious enough, the physical worker is being better and better paid and less and less hardly tasked, while just the reverse obtains in increasing ratios for those who live by the lower form of brain-work; so that the bribe to use the hand is growing daily, and pure mechanical labor, as opposed to that of the clerk, is being "levelled upward" with fortunate celerity.

Before attempting to indicate certain ways in which we as a people are overtaxing and misusing the organs of thought, I should be glad to have the privilege of explaining the terms which it is necessary to use, and of pointing out some of the conditions under which mental labor is performed.

The human body carries on several kinds of manufacture, two of which--the evolution of muscular force or motion, and intellection with all moral activities--alone concern us here. We are somewhat apt to antagonize these two sets of functions, and to look upon the latter, or brain-labor, as alone involving the use or abuse of the nervous system. But every blow on the anvil is as distinctly an act of the nerve centres as are the highest mental processes. If this be so, how or why is it that excessive muscular exertion--I mean such as is violent and continued--does not cause the same appalling effects as may be occasioned by a like abuse of the nerve-organs in mental actions of various kinds? This is not an invariable rule, for, as I may point out in the way of illustration hereafter, the centres which originate or evolve muscular power do sometimes suffer from undue taxation; but it is certainly true that when this happens, the evil result is rarely as severe or as lasting as when it is the organs of mental power that have suffered.

In either form of work, physical or mental, the will acts to start the needed processes, and afterwards is chiefly regulative. In the case of bodily labor, the spinal nerve-centres are most largely called into action. Where mental or moral processes are involved, the active organs lie within the cranium. As I said just now, when we talk of an overtaxed nervous system it is usually the brain we refer to, and not the spine; and the question therefore arises, Why is it that an excess of physical labor is better borne than a like excess of mental labor? The simple answer is, that mental overwork is harder, because as a rule it is closet or counting-room or at least in-door work--sedentary, in a word. The man who is intensely using his brain is not collaterally employing any other organs, and the more intense his application the less locomotive does he become. On the other hand, however a man abuses his powers of motion in the way of work, he is at all events encouraging that collateral functional activity which mental labor discourages: he is quickening the heart, driving the blood through unused channels, hastening the breathing and increasing the secretions of the skin--all excellent results, and, even if excessive, better than a too incomplete use of these functions.

But there is more than this in the question. We do not know as yet what is the cost in expended material of mental acts as compared with motor manifestations, and here, therefore, are at fault; because, although it seems so much slighter a thing to think a little than to hit out with the power of an athlete, it may prove that the expenditure of nerve material is in the former case greater than in the latter.

When a man uses his muscles, after a time comes the feeling called fatigue--a sensation always referred to the muscles, and due most probably to the deposit in the tissues of certain substances formed during motor activity. Warned by this weariness, the man takes rest--may indeed be forced to do so; but, unless I am mistaken, he who is intensely using the brain does not feel in the common use of it any sensation referable to the organ itself which warns him that he has taxed it enough. It is apt, like a well-bred creature, to get into a sort of exalted state under the stimulus of need, so that its owner feels amazed at the ease of its processes and at the sense of wide-awakefulness and power that accompanies them. It is only after very long misuse that the brain begins to have means of saying, "I have done enough;" and at this stage the warning comes too often in the shape of some one of the many symptoms which indicate that the organ is already talking with the tongue of disease.

I do not know how these views will be generally received, but I am sure that the personal experience of many scholars will decide them to be correct; and they serve to make clear why it is that men may not know they are abusing the organ of thought until it is already suffering deeply, and also wherefore the mind may not be as ruthlessly overworked as the legs or arms.

Whenever I have closely questioned patients or men of studious habits as to this matter, I have found that most of them, when in health, recognized no such thing as fatigue in mental action, or else I learned that what they took for this was merely that physical sense of being tired, which arises from prolonged writing or constrained positions. The more, I fancy, any healthy student reflects on this matter the more clearly will he recognize this fact, that very often when his brain is at its clearest, he pauses only because his back is weary, his eyes aching, or his fingers tired.

This most important question, as to how a man shall know when he has sufficiently tasked his brain, demands a longer answer than I can give it here; and, unfortunately, there is no popular book since Ray's clever and useful "Mental Hygiene," and Feuchtersleben's "Dietetics of the Soul," both out of print, which deals in a readable fashion with this or kindred topics.^[3] Many men are warned by some sense of want of clearness or ease in their intellectual processes. Others are checked by a feeling of surfeit or disgust, which they obey or not as they are wise or unwise. Here, for example, is in substance the evidence of a very attentive student of his own mental mechanism, whom we have to thank for many charming products of his brain. Like most scholars, he can scarcely say that he ever has a sense of "brain-tire," because cold hands and feet and a certain restlessness of the muscular system drive him to take exercise. Especially when working at night, he gets after a time a sense of disgust at the work he is doing. "But sometimes," he adds, "my brain gets going, and is to be stopped by none of the common plans of counting, repeating French verbs, or the like." A well-known poet describes to me the curious condition of excitement into which his brain is cast by the act of composing verse, and thinks that the happy accomplishment of his task is followed by a feeling of relief, which shows that there has been high tension.

One of our ablest medical scholars reports himself to me as having never been aware of any sensation in the head, by which he could tell that he had worked enough, up to a late period of his college career, when, having overtaxed his brain, he was restricted by his advisers to two or three hours of daily study. He thus learned to study hard, and ever since has been accustomed to execute all mental tasks at high pressure under intense strain and among the cares of a great practice. All his mind-work is, however, forced labor, and it always results in a distinct sense of cerebral fatigue,--a feeling of pressure, which is eased by clasping his hands over his head; and also there is desire to lie down and rest.

"I am not aware," writes a physician of distinction, "that, until a few years ago, I ever felt any sense of fatigue from brain-work which I could refer to the organ employed. The longer I worked the clearer and easier my mental processes seemed to be, until, during a time of great sorrow and anxiety, I pushed my thinking organs rather too hard. As a result,