86 



BIOLOGY OF DEATH 



tury as it is now. At age 47 the eighteenth century line 

 crosses that for the twentieth century, and with a few 

 trifling exceptions, notably in the years from 56 to 62, 

 the expectation of life for all higher ages was greater 

 then than it is now. We see in the eighteenth century 

 the same kind of result as was indicated in the seven- 

 teenth, only differing in degree. 



MILNCS CARLISLE HBO - HSTJ- UTL TABIZ 



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5 



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Fig. 20 — Comparing the expectation of life in the 18th century with that of the present time. 



It should be noted that all data as to mortality in the 

 seventeenth and eighteenth centuries lack the degree of 

 accuracy which one desires for purely scientific purposes. 

 By erring generally on the safe side these old mortality 

 tables did well enough for insurance purposes. But quite 

 different results as to the detailed values of life table 

 constants in these early periods are to be found in the 

 literature. For example, Richards constructed some 

 life tables from New England genealogical records, and 

 compared them with Wigglesworth's table, and also with 

 those of modern times. His general conclusion, for the 



