Figure 4. To investigate whether the continuous decrease in the percentage of the survivors, going hand in hand with the increase of maternal conceptions, is caused by the constitutional inferiority of the offspring as the numerical position increases, Bluhm has established, in dealing with her material, the loss for each numerical position (first, second, third, etc., conceptions respectively). If this were the case, Curve A, which gives the loss according to the frequency of conception in each marriage, would have to be identical with Curve B, which gives the loss of first, second, and third, etc., conceptions, but this is by no means the case, for only at a very high numerical position of the conception the curves begin to be parallel. This proves that Hamburger's "the percentage of the survivors gets smaller in proportion as the conception number increases" is not a biological law but only expresses a social phenomenon. With the increasing number of children there is a decrease in the value of each individual childlife. The mother is less careful about avoiding miscarriages; she devotes, and must necessarily devote, less care to each child; and the risk of infectious diseases which are a frequent cause of death during infancy increases. [Sidenote: C 53] How little the increasing mortality of the later born children up to the tenth child is based on a biological law is shown in Figure C 53. +Numerical position of birth and infant mortality up to the age of five in princely families+, by Ploëtz; 463 seventh to ninth children show the same mortality as the 614 first born. Pearson endeavored to prove a high degree of inferiority in the first born, physically and intellectually as well as morally. But his results are very open to attack, as Weinberg has recently shown; one is reminded of Pearson's results in Crzellitzer's Figure C 54--first and later born. Crzellitzer writes thus about this--"A +high degree of myopia+ is +more frequent amongst first born+ than among later children. The disadvantage of the first born in respect of myopia is based on a greater hereditary taint and on no other factor. Where there is no hereditary taint about one quarter to one-third are affected, no matter whether first, second, third, etc., born. Also in well-to-do families, where the age of fathers at the time of procreation is materially higher, the first born are more frequently myopic than their brothers or sisters." [Illustration: First and Later-Born. Percentage of Frequency of Extreme Short-sightedness. (After Dr. Crzellitzer.) Child 1st 2nd 3rd 4th 5th 6th 7th 8th ============================== ==== ==== ==== ==== ==== ==== ==== ==== 1,246 children from 216 working-class families. 46.4 33.7 31.4 26.6 26.5 26.0 15.5 18.7