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THE NATIONAL GEOGRAPHIC MAGAZINE 



Photograph by J. Horgan, Jr. 



CHEMICAL FIRE) - FIGHTING APPARATUS PGR MINK PROTECTION 



Every precaution is taken to protect mines from fire disaster. In the Carbondale country 

 of the anthracite area there is a mine that has been burning for years. It has never been 

 found possible to check the flames. Occasionally there are cave-ins which startlingly suggest 

 the bottomless pit. Restoring a mine after a serious fire is often a matter of years. 



which live today, but the survivors are 

 pigmies, measured by the giant statures 

 of their antediluvian ancestors. Trees 

 that rose to a height of fifty feet and pos- 

 sessed trunks two or three feet in diam- 

 eter are now represented by plants with 

 stems a fraction of an inch in circumfer- 

 ence and a foot or so high. 



AMAZING COAL-AGE VEGETATION 



Nor was the difference in luxuriance 

 as compared with today less great than 

 the difference in size. There was the 

 great lepidodendron, a club moss which 

 grew from forty to fifty feet high ; its 

 largest existing descendant reaches a 

 height of not more than three feet. There 

 was the sphenopteris, a giant fern raising 

 its head like a palm tree ; there were the 

 calomites, cousin of the modern horsetail, 

 which grew in dense jungles; and there 

 were even grasses which grew to the 



height of a forest of twenty years' 

 growth. 



Perhaps the most striking of all coal- 

 age vegetation was the beautiful sigillaria, 

 a monarch of the carboniferous forests, 

 whose trunk often swelled to five feet in 

 diameter and possessed a bark that 

 seemed studded with sealing-wax impres- 

 sions. 



In a single mine in England thirty of 

 these trees were found standing in their 

 natural position in an area fifty yards 

 square, the wood of each petrified and the 

 bark turned to coal. In some cannel-coal 

 mines whole trees have been found, with 

 roots, branches, leaves, and seeds com- 

 plete, all converted into the same quality 

 of coal as that surrounding them. 



Those were happy days in the vegeta- 

 ble kingdom. Plant life was quickened 

 as animal life is stirred by the ozone of 

 the sea, for the air was laden with unim- 



