PLANT-MUMMIES. 239 



regions ; and there, too, sleeps the animal world of those 

 days. Here is the big lizard, not one of her tiny scales 

 wanting ; there is the colossal shark, in all his huge dimen- 

 sions. They are all there, every plant and every animal, 

 uninjured by the unsparing tooth of time. Not a line 

 is effaced, not a letter is illegible in this great book of 

 nature. 



Man soon determined to employ the new power thus 

 granted him ; but, although Marco Polo tells us that the 

 Chinese used coals as far back as his own time (1270) 

 Europe did not employ them until about a hundred years 

 ago. Then, however, began the reign of the new agent 

 in man's rule over the earth, and the strange spectacle 

 is presented in some places, that the mummies of long- 

 forgotten trees, reared in regions once tropical, but now 

 ice-bound, must serve to warm the houses of men and 

 to force tropical fruits in northern climates. Now, coal 

 as fuel, drives the railway train and the steamer ; it works 

 in every factory, it burns on every hearth ; it is to Eng- 

 land more precious than gold and costly jewels. 



Its gases, the terror of the poor miner who but too 

 often falls a victim of the terrible "fire-damps," have been 

 changed from a death-bringing enemy into a most useful 

 servant. To drive them out from the mines, they were 

 at first conveyed in tubes to the outer air. By accident 

 it was found that they could ignite, and from this simple 

 attempt to effect an escape for a nuisance, man derived 

 the light which now rivals the noonday -brightness, and gives 

 peace and security even to overgrown cities. 



