50 Our Field and Forest Trees 



metal he was after. His sole interest was in the 

 little spot where he had found ore and staked his 

 claim. He looked upon the forest as a hindrance 

 to be cleared away as soon as possible, and so he 

 set fire to the beautiful evergreens which covered 

 the mountain slopes and darkened the valleys. He 

 had not time to check the spread of the flames, 

 and so the fire burned on until mile after mile of 

 forest had been destroyed. 



Now the miner knows that trees are his best 

 friends, for logs are used in great quantities to 

 support the roofs of mines after coal or ore has 

 been removed. Indeed, one very important ques- 

 tion in deciding the value of a mine is this ques- 

 tion of timber. The mining engineer wants to 

 know where timber can be obtained, how far it 

 must be brought, and what sort it is; for in the 

 mine-damp some woods decay sooner than others. 

 Red cedar is a favorite tree with mining engineers, 

 and next come the bald cypress, larch, and pine. 

 The trunks of these trees are straight, and the 

 resin in their wood helps to preserve it from decay. 



Many trees are cut every year for the mine 

 workings of the United States. Though coal 

 mines have been the means of sparing firewood, 

 and thus, in one way, have saved the lives of trees, 

 they are none the less devourers of the forests, for 

 in the damp of a coal mine timbers last but a very 

 short time (Fig. 17). 



Nowadays logs to be used in mines or for tele- 



