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THE NATIONAL GEOGRAPHIC MAGAZINE 



uate the naval stores industry. We can 

 practically stop forest fires at a cost 

 yearly of one-fifth the value of the mer- 

 chantable timber burned. 



WATER POWER NEGLECTED 



The sole source of our fresh water is 

 rainfall, including snow. Our mean an- 

 nual rainfall is about 30 inches ; the quan- 

 tity about 215,000,000,000,000 cubic feet 

 per year, equivalent to ten Mississippi 

 Rivers. 



Of the 70,000,000,000,000 cubic feet 

 annually flowing into the sea, less than 

 I per cent is restrained and utilized for 

 municipal and community supply; less 

 than 2 per cent (or some 10 per cent of 

 that in the arid and semi-arid regions) is 

 used for irrigation ; perhaps 5 per cent is 

 used for navigation, and less than 5 per 

 cent for power. 



The water power now in use is 5,250,- 

 000 horse power; the amount running 

 over government dams and not used is 

 about 1,400,000 horse power; the amount 

 reasonably available equals or exceeds 

 the entire mechanical power now in use, 

 or enough to operate every mill, drive 

 every spindle, propel every train and 

 boat, and light every city, town, and vil- 

 lage in the country. 



SAVING OE LIVES 



Since the greatest of our national as- 

 sets is the health and vigor of the Ameri- 

 can people, our efficiency must depend 

 on national vitality even more than on 

 the resources of the minerals, lands, 

 forests, and waters. 



The average length of human life in 

 different countries varies from less than 

 25 to more than 50 years. This span of 

 life is increasing wherever sanitary sci- 

 ence and preventive medicine are applied. 

 It may be greatly extended. 



Our annual mortality from tubercu- 

 losis is about 150,000. Stopping three- 



fourths of the loss of life from this 

 cause and from typhoid and other prev- 

 alent and preventable diseases, would in- 

 crease our average length of life fifteen 

 years. 



There are constantly about 3,000,000 

 persons seriously ill in the United States, 

 of whom 500,000 are consumptives. More 

 than half this illness is preventable. 



If we count the value of each life lost 

 at only $1,700, and reckon the average 

 earning lost by illness as $700 a year for 

 grown men, we find that the economic 

 gain from mitigation of preventable dis- 

 ease in the United States would exceed 

 $1,500,000,000 a year. This gain, or the 

 lengthening and strengthening of life 

 which it measures, can be had through 

 medical investigation and practice, school 

 and factory hygiene, restriction of labor 

 by women and children, the education of 

 the people in both public and private 

 hygiene and through improving the ef- 

 ficency of our health service, municipal, 

 State, and national. 



The permanent welfare of the nation 

 demands that its natural resources be 

 conserved by proper use. To this end 

 the States and the nation can do much 

 by legislation and example. By far the 

 greater part of these resources is in pri- 

 vate hands. Private ownership of nat- 

 ural resources is a public trust; they 

 should be administered in the interests 

 of the people as a whole The States 

 and the nation should lead rather than 

 follow in the conservative and efficient 

 use of property under their immediate 

 control. But their first duty is to gather 

 and distribute a knowledge of our natural 

 resources and of the means necessary 

 to insure their use and conservation, to 

 impress the body of the people with the 

 great importance of the duty, and to pro- 

 mote the cooperation of all. No agency, 

 State, Federal, corporate, or private, can 

 do the work alone. 



