The youth who works daily in a given line at the gymnasium as much expects that, before the year is over, not only will the muscles used decidedly increase in strength, but in size and shapeliness as well, as he does that the year's reading will improve his mind, or a year's labor bring him his salary. It is an every-day expression with him that such a fellow "got his arm up to" fifteen, or his chest to forty-odd inches, and so on. He sees nothing singular in this. He knows this one, who in a short time put half an inch on his forearm, or an inch; that one, whose thigh, or chest, or waist, or calf made equal progress. Group and classify these gains in many cases, and note the amount of work and the time taken in each, and soon one can tell pretty well what can be done in this direction. Few of our gymnasiums are so kept that their records will aid much in this inquiry, simply because the instructor either has no conception of the field before him, or, if he has, for some reason fails to improve the opportunity. Look at what Maclaren effected (as described by him in his admirable "Physical Education"), not with here and there an isolated case, but with both boys and men turned in on him by the hundred, and in all stages of imperfect development! Take it first among the boys. Under systematic exercise, W----, a boy at Radley College, ten years old in June, 1861, had, seven years later, increased in height from 4 feet 6-3/4 inches to 5 feet 10-3/4 inches, or a gain of 16 inches in all; in weight from 66 pounds--light weight for a ten-year-old boy--to 156 pounds; far heavier than most boys at seventeen; showing an advance of 90 pounds. His forearm went from 7-1/4 to 11-3/4 inches--very large for a boy of seventeen, and decidedly above the average of that of most men; his upper arm from 7-1/2 inches to 13-3/8--also far above the average at that age; while his chest had actually increased in girth from 26 inches--which was almost slender, even for a ten-year-old--to 39-1/2 inches, which is all of two inches larger than the average man's. His description of this boy was: "Height above average; other measurements average. From commencement, growth rapid, and sustained _with regular and uniform development_. The whole frame advancing to great physical power." Another boy, H----, starting in June, 1860, when ten years old, 4 feet 6-1/4 inches high, and weighing 73 pounds--much heavier than the other at the start--in eight years gained 13-1/2 inches, making him 5 feet 7-3/4 inches--of medium height for that age. He gained 71 pounds in the eight years, and at 144 pounds was better built than W---- at 156; for, though his forearm, starting at 8 inches, had become 11-1/2, a quarter of an inch less than W----'s, yet his upper arm had gone from 8-3/4 to 13-1/2 inches, or one-eighth of an inch larger, while his chest rose from 28-1/4 to 39 inches--within half an inch of the other's, though the latter was 3 inches taller.