Lindsay — Annual Rainfall and Temperature of TJ. 8. 75 



Louisiana, Texas and Oklahoma. The Western division 

 comprised the remaining states to the west. 



In the year 1896 the total rainfall on the Northeast 

 section was 98.9 cubic miles; on the Southeast, 199.7; on 

 the North Central, 363.0; on the South Central, 308.8, and 

 on the Western, 326.0, making a total for the United 

 States of 1,296.4 cubic miles. This is about thirty times 

 as much as falls in Missouri in one year. The greatest 

 annual volume of precipitation during the years consid- 

 ered was in 1902 when 1,396.9 cubic miles fell. In 1894, 

 the year of minimum fall, there was only 1,199.1, a dif- 

 ference of about 200 cubic miles. 



The curve P shows the variation of precipitation from 

 year to year. The average for these fourteen years is 

 1,308.0 cubic miles. One cubic mile of water weighs 4.58 

 xlO^ tons. This great volume of 1,308 cubic miles ap- 

 pears more gigantic when we think of its weight — 6.00x 

 10^^ tons for the year. A tremendous amoimt of work 

 would be required to lift this mass from the surface of 

 the earth to the height from which it falls again as rain. 

 Taking the average height of the raincloud as Yz mile, it 

 would require 317x10" foot-lbs. of work. 18,270,000 en- 

 gines of 100 h. p. each would be kept in operation day 

 and night to elevate the water to the clouds as rapidly 

 as it falls on the surface of the United States. If we 

 consider the heat required to vaporize it we find it would 

 require the combustion of 5x10^^ tons of anthracite per 

 annum to furnish enough to change the water into vapor 

 at a temperature of 68° F. 



The average yearlj^ temperature for the whole coun- 

 try was obtained as follows: The average for each state 

 was found, just as in the case of the rainfall, by averag- 

 ing the values of the several station reports, together 

 with interpolated values, multiplying the average by the 

 area of the state, adding these products for all the states, 

 and dividing the sum by the area of the whole United 

 States. 



This gives for the average temperature of the United 



