THE VALUE OF PURE WATER 



75 



100 gallons per capita), or $0.10 per capita per year for each unit 

 reduction of the typhoid fever death-rate per 100,000. In other words 

 the decrease in the typhoid death-rate per 100,000 divided by 10 gives 

 the increased vital assets of the community in dollars per capita per 

 year. Thus in the case of Albany, above given, the reduction in the 

 typhoid fever death-rate was 78 per 100,000. On the basis of 10 cents 

 per capita per unit decrease, this would amount to $o. ioX 78X95,000 

 = $741,000 per year, assuming a per capita consumption of 100 gallons 

 daily, or $450,000 for a per capita consumption of 165 gallons daily, 

 which is the figure stated above. 



Looking at the matter in another way, it may be said that the puri- 

 fication of a polluted water is a sort of life-insurance for the people, 

 the value of which is equal to 10 cents per capita for each unit decrease 

 in the typhoid fever death-rate per 100,000 which it brings about. 

 Such a sum capitalized represents a large amount of money. In 

 Albany, for example, where the typhoid fever death-rate has been 

 reduced 78 per 100,000, the annual saving of life- value would be $7 . 80 

 per capita. Capitalized on the basis of an annual life-insurance 

 premium of $17 per thousand, this would represent an insurance 

 policy of about $460 per year for each inhabitant, or $2,300 for each 

 head of a family. 



Physical quality. The figures of Table 8 show the effect of filtra- 



TABLE 8. 



