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years is (his, lhal the Iota] number of data for comparison is rather 

 small, and thai there remains an uncertainty as to whether really 

 the increased mortality, appearing from Ihese means, occurred in the 

 same years in which also the number of summerdays was largest. 

 For this reason we have compiled from the "Ned. Staatscourant" 

 the numbers expressing the death-rate of children less than one year 

 of age for the period 1881—1905, both for Utrecht and Groningen; 

 we have expressed the monthly values in percentages of one twelfth 

 of the yearly death-rate, and compared these data after the method 

 of the preceding §§, by comparing the deviations from the means 

 for the period 1881—1905 respectively 1891 — 1905, with the 

 deviations of the number of summerdays between .Ma\ L6 th and 

 June 15 th etc. 



The results are given in the following tallies. 



GRONINGEN 1891—1905 



