Another cause of this stupefying process is the rigid system by which most large schools are conducted, where promotions, from one class to another, can take place, say, once a year, the pupil who, on examination, falls short of the required per cent of correct answers, being forced to review the work of the entire previous year before going on. More elasticity, more fluidity, as it were, is sadly needed in our system of public school education before this evil will be to any great extent modified.[20] It would be a waste of time to say that one ought not to be overworked, were it not that some persons always seem to imply that any intellectual work is overwork. It would seem equally superfluous to say that for intellectual health there ought not to be any surplus energy, for the latter statement seems as axiomatic as the former. The problem with which educators are chiefly concerned is that of fully employing the energies without overtasking them. If the dividing line between _enough_ and _too much_ could be determined as exactly as the Mississippi River marks the series of lowest points where the eastern slope of the Rocky Mountains meets the western slope of the Alleghenies, our work as teachers were easy indeed. Teaching, however, is not the only profession where such unsolved problems exist, for individual cases, and we teachers are thus but a part of a noble army of professional workers, so we take heart of grace, and are not ashamed. But the fact remains to be considered that the work of school education is, as the result of unavoidable destiny, in America, passing very rapidly into the hands of women. We may deplore this, but we cannot prevent it. The last census showed that the number of women teachers in the United States stands already to that of the men as 123,980 to 78,709, and the ratio is daily increasing. There is no other country in the world, then, where it is so all important that the girls should receive a complete education. In one view, this tendency of the times is of great value. The years spent in teaching are often the most valuable training for the work of the mother. No other employment calls for a greater exercise, and hence, a greater development, of the directive power, and of the knowledge of human nature which will enable her well and wisely to direct her children, successfully to grapple with the "servant problem," and to sweep a large circle of details within the compass of generalized rules. She has learned what industry means, not, as was said by a Christian writer of the thirteenth century, only "to pray to God, to love man, to knit and to sew." She has not "everlastingly something in her hand, though no one profits by her labor, and she is reduced to look for her sole reward in civil speeches made for useless gifts, or insincere praise of household ornaments that are in everybody's way," covers, and covers for covers, and covers for covers of covers.