234 



Popular Science MoiifJiIi/ 



This big dump of culm coal is on fire, although there are no visible signs of it. A trench is 

 being cut across the pile to restrict the fire to its present field and prevent it from spreading 



Coal-Dust "Mountains" are Now 

 Repositories of Wealth 



IN the anthracite mining region of 

 Pennsylvania there are real ranges 

 of hills, almost mountains, of pure coal. 

 These are the piles of culm or coal-dust 

 screenings, which, imdcr former methods 

 of mining, were thrown out as so much 

 waste. There are millions of tons of 

 this culm, and modern furnaces arc 

 now using it. Culm is not only screened 

 and burned as by-coal, a "dust," but is 

 also pressed into briquettes. Modern coal- 

 dust burning locomotives are using it as 

 pulverized fuel. As such it is of perma- 

 nent value. 



The photograph shows a large culm 

 dump near Scranton, Pennsyhania, 

 wliich has caught afire. Once a fire 

 gains good lieadway it is extremely difli- 

 cult to extinguish; it burrows down 

 into the very heart of the pile and then 

 works its way along laterally. A few 

 years ago this culm pile would have been 

 allowed to burn itself out as a worthless 

 property. Now it is being sa\-ed, as 



shown in the picture, by cutting a trench 

 across the pile to check the progress of 

 the fire. Although the photograph gives 

 no \isible e^■idence of a fire, proximity to 

 the radiating heat of the pile would prove 

 to liie onlooker tliat the interior is a 

 veritable inferno. 



A Damaged Lock - Gate Repaired by 

 Its Own Water 



WATER swirling out of the locks at 

 Suult Ste. Marie damaged one of 

 the gates so badly that the canal engi- 

 neers despaired; but the trouble was sin- 

 gularly righted by allowing water to 

 rush in again. A ship had jiassed out of 

 the canal, and the lock was allowed to 

 drain, but one of the gates was closed 

 too soon, was caught in the rusliing 

 water, and bulTeteil so rougiih- that the 

 top was s|)rung more than a foot out of 

 plumb. Several unsuccessful attempts 

 were made to repair (he sagging gate b>' 

 means of jacks and turntables. Mean- 

 while, a long line of ships from the North 

 and South was inipalicntly gathering. 



