38 ILLINOIS ACADEMY OP SCIENCE 



ones, why the state should provide the necessary machinery 

 for registering these events? The reason why the physiciar, 

 is interested, is because birth and death registration is, as it 

 has aptly been styled, "the book-keeping of humanity." It is 

 only by carefully recording all births, by observing the num- 

 ber and percentage of births and deaths over a large area 

 with a large population for a long period of time, that any 

 accurate figures can be secured regarding the average birth 

 or death rate per 1.000 or per 10.000 of population, the rela- 

 tive birth and death rate in ditiferent localities, races and per- 

 iods of time, the relative death rate in different periods of 

 life, the average duration of life, and what insurance men 

 call the ''expectation of life", the relative proportion of deaths 

 occurring from different causes and the relative frequency of 

 disease. In short, the only way by which any accurate fig- 

 ures can be secured, on which can be based any statements 

 regarding vital facts, is the systematic registration of births 

 and deaths. 



It is, accordingly, only in a state or a community in 

 whch births and deaths are carefully observed and re- 

 corded, and in which the recording system and the 

 nomenclature used are uniform with those of other 

 states and countries that the community can learn 

 whether it is gaining or losing in population, wheth- 

 er the birth rate is increasing or decreasing, whether the 

 death rate, either as a whole, or from some single cause, is 

 increasing or not, whether the eflforts to improve sanitary 

 conditions are successful or not, and what is the relative 

 value of different methods. Just as a business man who kept 

 no books would be unable to determine his financial condi- 

 tion, or whether he was making or losing money, so the health 

 officer who is without carefully recorded vital statistics is 

 equally at a loss. General impressions are notoriously un- 

 trustworthy. A community may believe that is is unusually 

 healthy, yet a careful record of deaths may show that the 

 death rate is fifty, seventy-five or even one hundred per cent, 

 in excess of the normal, and this from thoroughly preventable 

 causes. Dr. W. S. Rankin, Secretary of the North Carolina 

 State Board of Health, says: "Applied vital statistics is the 

 most essential and powerful remedy for the improvement of 

 the health or social organizations for bringing about sanitary 

 reforms, for preventing diseases, for postponing death, and 

 for adding years to the duration of the average life that we 

 possess." Just as accurate book-keeping with carefully drawn 

 balance sheets and an exhaustive analysis of expenses will 

 enable the merchant to save money, so carefully kept records 

 of mortality will produce longer life. Dr. Rankin illustrates 



