HOW OUR COAL WAS MADE 



What was happening on the surface of the earth 

 during all that time when the life in the sea was 

 spreading and growing and being pressed between 

 the leaves of nature's book? Did the dry land re- 

 main bare and lifeless? 



Oh, no. The dawn of life had come there too, at 

 last. Earth's garment was beginning to creep over 

 the rocks and to cover the marshy places with 

 green. The same lowly plants that start to clothe 

 the bare rocks now, the lichens and the mosses, 

 long ages ago commenced to creep over those 

 water- worn rocks. Tiny ferns began to tuck their 

 little feet into the cracks and crannies of the cliffs. 

 And in the hollows, where the waters of the streams 

 had spread out with their load of pebbles and sand, 

 rushes sprang up and made a mass of green. 



The earth and the air were warm and moist, so 

 that these new forms of life grew and increased in 

 number and in size, as did the shells and the fishes 

 in the sea. The small rushes that first started to 

 grow in the shallow pools changed as ages rolled 

 on, so that by the time the large fishes swam pon- 

 derously about in the cooling seas these rushes had 

 grown so large in the wet clay that they made great 

 dark forests of tall, strange-looking trees along the 

 margin of the seashore. 



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