That the unit of measurement should be as small as possible, owing to the tendency of many observers to record a measurement at the nearest whole number, the metric system was adopted.
In computing the normal height, weight, and chest-girth, I used, simply for comparison with and in verification of my own deductions, data compiled from various sources, representing over a million measurements of each of these parts.
The directions for the use of the chart are very simple: To find the standing of an individual in relation to the total number examined, ascertain which one of the perpendicular lines, at its junction with the horizontal line, is intersected by the dotted line indicating his standing. For instance, if his line, at its junction with the horizontal line leading from the weight, intersect the perpendicular line immediately under the figure 20, it would, indicate that 80 per cent of all those examined surpassed him in weight, while the complement of this, or 20 per cent, failed to surpass him.
If, however, his line, where it intersects the line of measurement, fall on the line at the right or left of one of the numbered perpendicular lines, add or subtract 2 1/2 per cent, unless it fall outside of either the figure 10 or 90, in which case but \\ per cent should be reckoned.
As a rule, all the measurements of a small person fall to the left, and all the measurements of a large person fall to the right, of the normal line.
If strong for his age, weight, height, or development, the part of his line that indicates the strength will be on the right of the part that indicates the age, weight, or measurement.
Symmetry will be determined by the degree to which his line approaches the perpendicular.
Asymmetry, by the extent to which his line departs from the perpendicular.
To ascertain his development as compared with others, observe the intersection of his line with the lines of muscle measurements.
His development, as compared with his capacity for development, will be shown by the difference between the muscle measurements and the bone measurements for corresponding parts; as the knee, elbow, wrist, etc.
Figs. A, B, represent a young man of English descent, twenty-three years of age, weight, 149 pounds, and height 5 feet 6 inches.
Upon referring to Chart I.,* where his measurements have been plotted, the relative standing of the young man as compared with the total number examined is readily observed, as well as the relation which every part of the individual bears to every other part.
His line, at its juncture with the horizontal line leading from the age, falls to the right of the perpendicular line immediately under the figure 85. This indicates that 12 1/2 per cent of all those examined surpassed him in years, while the complement of this, or 87 1/2 per cent, failed to surpass him.
The weight falls in the 82 1/2 per cent and the height in the 20 per cent class. The height of knee and pubic arch falls to the left, and the sitting height and height of sternum fall to the right of the line indicating the full stature. This discrepancy indicates that his diminutive stature is due to the shortness of the lower extremities, and that the upper part of the legs is too short for the lower part.
* This chart is obviously limited in its application to those who have been examined according to the system of measurements herein described. More explicit directions will be furnished by the author to any one desiring to pursue the same method.
The girth of head is above the 85 per cent line, and the girth of the neck and chest above the 97 1/2 per cent line.
The measurements of the waist and hips fall off a little proportionally from those of the chest; but it will be observed that all of the girths are unusually large for the height, indicating a fine muscular development.
The depth of chest and abdomen, and the breadth of the head, neck, waist, and hips, are relatively small; but the breadth of the shoulders approaches very near to the maximum.
The length of the upper arm is a trifle short, as shown by the measurements from the shoulder to the elbow. The forearm and hand are also below the normal in length, but slightly longer in proportion than the upper arm. The left forearm and hand are half a centimetre shorter than the right. This difference is made apparent by the variation in the points denoting the right and left elbow-tips. There is also a discrepancy in the length of the feet.
His horizontal length is about the same as the height; while the stretch of arms is appreciably greater, reaching, as it does, to the 50 per cent line. This may seem slightly paradoxical, as the length of the forearm and upper arm is below the average, but the increased extension of the arms, when measured horizontally from finger-tip to ringer-tip, is due to the great breadth of the shoulders. The capacity and strength of lungs, though fairly good, are not what might be expected from the prominence of the chest measurements. Referring to the accompanying illustrations, however (Figs. A and B, back and side views), we find that the large chest-girth is undoubtedly due to the development of the chest-muscles, and to those of the upper back, while the region below the nipples is somewhat narrow and contracted. It will also be observed that the girth of the chest (full) is proportionately below that of the chest in repose. This indicates that the power of inflation is less than it ought to be.
The strength of the back accords with the measurements of the waist, and that of the arms and chest with the measurements of these parts; but the strength of the legs is somewhat greater than we should have reason to look for from the development presented at the thighs and knees.