PROTECTION 137 



burned over and by the number of fires. Studies 

 of this kind yield positive information on what areas 

 of each Forest are particularly liable to lightning 

 fires, to camp fires, and to incendiary fires. With 

 this knowledge the Forest Supervisor can plan and 

 distribute his men and funds more intelligently; 

 they tell him during what period he can expect the 

 most trouble, and therefore must have the greatest 

 number of fire fighters at his command. It is 

 scientific study like this that is doing more than 

 anything else to solve the fire protection problem 

 in the Western States. 



Relation of Forest Fires to the Weather. In 

 cooperation with the United States Weather 

 Bureau, the Forest Service studies weather condi- 

 tions in relation to forest fires. Weather forecasts 

 have been sent to each Forest Supervisor through- 

 out the fire season, informing him of the probable 

 weather conditions. The velocity and duration of 

 the wind, the temperature, the precipitation, and 

 the relative humidity are all factors which greatly 

 affect the inflammability of the forest. Forest Su- 

 pervisors have been informed in these forecasts of 

 what are known as emergency conditions, that is, 

 an unsual and abnormal combination of weather 



