392 SCIENCE OF HOME AND COMMUNITY 



through vaccination from the years 1875 to 1886, taking the above 

 figure as the average population for these years. 



7. Do the same for Holland, whose population in 1880 was 

 nearly 4,000,000. 



8. Estimate the number of lives that might have been saved in 

 Austria from the years 1875 to 1884 if vaccination had been made 

 compulsory as it was in Prussia. To do this first find the average 

 annual death rate in Austria for the years 1875 to 1884. Subtract 

 from this the average annual death rate in Prussia for the same years. 

 What does this difference represent ? The population of Austria in 

 1880 was about 22,000,000. Remembering that the death rate 

 means the number of deaths per 100,000 inhabitants, estimate the 

 number of lives that might have been saved by vaccination during 

 the years 1875 to 1884, taking the above figure as the average 

 population. 



COMMUNITY PROJECT 2 



Purpose. To study the death rate in your own state and 

 locality for different diseases. 



Directions, i. Secure the latest report of the state board 

 of health. From a study of the statistics of deaths compute the 

 per cent of deaths from the ten most common diseases. Arrange 

 these in the order of the per cent of deaths. 



2. Obtain the reports from the city health officer of the deaths 

 in your city or county and work out the per cent of deaths from 

 the ten most common diseases. 



3. If possible get the figures from some neighboring city and 

 compare the two. 



SUPPLEMENTARY QUESTIONS FOR CLASS DISCUSSION 



1. How can such small organisms as bacteria have so much 

 influence on human life ? 



2. What is the relation of temperature and moisture to the 

 growth of bacteria ? 



3. What are the chief means by which disease bacteria 

 leave the body ? 



4. How may they enter the body ? 



