OCR Rendition - approximate

284 he corroborates his assertion. Three of the series in them refer to the heights of Americans, French, and Belgians respectively, and the fourth to the strength of Belgians. In each series there are two parallel columns, one entitled " observed," and the other " calculated," and the close conformity between each of the pairs is very striking. Scale of American Soldiers France Belgium, Quetelet. Heights. (25,878 Observations). (Hargenvilliers). 20 years' Observations. Observed. I Calculated. Observed. Calculated. Observed. Calculated. metres. 1 3 1.90 1.90 7 5 I } 1 -87 14 13 .. 1 84 25 28 3 2 3 81 45 52 25 7 7 7 .79 99 84 16 14 14 76 112 117 82 82 84 28 73 138 142 55 55 48 53 70 148 150 88 87 102 107 68 137 137 114 118 138 136 65 93 109 144 140 129 150 62 109 75 140 145 162 150 60 49 45 116 132 106 136 57 14 24 .. 105 110 107 54 8 11 73 53 51 1 4 44 28 48 .. 1 24 147 14 45 .. .. 286 11 7 42 .. .. 4 3 39 .. .. 2 1 -36 .. • 1 _ 1000 1000 1000 1000 1000 1000 Degrees of Lifting Power of Belgian Men. Dynamometer. Observed. Calculated. 200 1 1 190 9 10 180 1 170 23 23 160 I 150 32 32 } 140 130 22 23 } 120 110 12 10 100 J 90 1 1 100 100 1877.] on Typical Laws of Heredity. 285 These tables serve another purpose; they enable those who have not had experience of such statistics to appreciate the beautiful balance of the processes of heredity in ensuring the repetition of such finely graduated proportions as those that the tables record. The outline of my problem of this evening is, that since the characteristics of all plants and animals tend to conform to the law of deviation, let us suppose a typical case, in which the conformity shall be exact, and which shall admit of discussion as a mathematical problem, and find what the laws of heredity must then be to enable successive generations to maintain statistical identity. I shall have to speak so much about the law of deviation, that it is FIG. 1. absolutely necessary to tax your attention for a few minutes to explain the principle upon which it is based, what it is that it professes to VOL. VIII. (No. 66.) x Mr. Francis Gallon [Feb. 9, CIibPDF - www.fastio.com