He dwells at length upon conditions in the army, the attempt which he had made to meet them with his military system, and the results secured (pp. 64-94). “Now if all this arrangement and method were considered necessary in the organization of the bodily exercise of full-grown men—men of mature frame and hardy habit, and at the period of life when all the physical energies are at their highest point of power, at least as much precaution and forethought and method, it would be expected, would be adopted on its administration with boys and lads at school, whose frames are all incomplete and impressionable in the highest degree; capable of being affected for good or evil by every surrounding agency. But what are the facts? Except the two Military Colleges of Woolwich and Sandhurst, and Radley College, not one of our large educational establishments is provided with a regularly organized Gymnasium with properly qualified teachers.... In our day if gymnastics mean anything,—that is, anything worth the serious thought of parent, teacher, or pupil,—they mean a gradual, progressive system of physical exercise, so conceived, so arranged, and so administered, that it will naturally and uniformly call forth and cultivate the latent powers and capacities of the body, even as the mental faculties are developed and strengthened by mental culture and mental exercise.” In the appendix Maclaren illustrates certain forms of growth and development, regular and irregular, at different ages (A. Figs. 1-14); gives tables showing the state of growth and development between the ages of ten and eighteen years (B), and of men on arriving at the University (C); one which shows the influence of systematized exercise, extending over periods of several years, on boys of different conditions of growth and development, and on men of different degrees of physical power (D); and others containing measurements of non-commissioned officers before and after their course of training under him (E), and corresponding figures for youths at the Royal Military Academy, Woolwich (F), and for two pupils of his own (G); explains his system of measurements (H), goes into some detail regarding the construction and requirements of gymnasia (I), and closes with tables of best performances at certain athletic meetings (K). It is this practical demonstration of what regular exercise will accomplish, as well as his impressive setting forth of the need for it, that has caused his book to be so often quoted and makes it one of permanent value.