792 



AMERICAN MEN OF SCIENCE 



and the number of children is only 29. 

 The data also show that successive polyg- 

 amy through divorce is unusual among 

 scientific men. 



the a^e of twenty-nine, 298 of the fathers 

 and 328 of the mothers between twenty 

 and twenty-nine. The scientific men them- 

 selves married at the average age of 29.5 



In Table V. data are given in regard to 

 the age at marriage and the size of family 

 of our leading scientific men and of their 

 parents.^ The fathers married at the 

 average age of 28 years and the mothers 

 at the average age of 22.9 years. The 

 median ages are naturally lower than the 

 averages ages, as maiTiage can be post- 

 poned beyond the average longer than it 

 can precede this average. The distribu- 

 tion of ages is also shown in the table. 

 Five of the fathers and 85 of the mothers 

 married under the age of twenty, 137 of 

 the fathers and 27 of the mothers beyond 



5 The data are for itlie 440 oases in which the 

 families of the scientific men were "completed" 

 and in which there were no remarriages either of 

 the scientific men or of their fathers. The fam- 

 ilies were taken as completed when the wife was 45 

 or older, when there had been ten years of married 

 life without a child or when the period since the 

 birth of the last cMld added to the mother's age 

 is at least 45. Some of the families are then not 

 absolutely completed, but the births would be very 

 few. None of the 11 women who were more than 

 39 at marriage had children, although newly mar- 

 ried women of this age are more likely than others 

 to bear them. A larger error is due to the selec- 

 tion of families, as those having few or no children 

 would be more likely to be completed. The 211 

 incomplete families have on the average 1.90 chil- 

 dren, which is about the same as for the comjileted 

 families of parents of the same age. 



years and their wives were on the aver- 

 age 26.6 years old. The sons married 

 about one and a half years later than 

 their fathers and their wives nearly four 

 years later than the mothers. There is 

 a statistical anomaly in this comparison, 

 especially as regards the mothers, for 

 women who married late would have 

 few children or none, and the average 

 age of the mothers would thus be re- 

 duced as compared with the wives. The 

 differences are partly due to the fact that 

 all the scientific men and only part of the 

 fathers belong to the professional classes; 

 and tliere has probably been an increase 

 in the age of marriage of the professional 

 classes in this country' ; but the figures 

 show that any such increase must be small. 

 Bertillon gives the following figures for 

 the average age at marriage in the period 

 1896-1900: 



