94 RAMBLES AND REVERIES. 



and climate to what it now is. Enormous submarine 

 volcanoes, such as must have been in almost con- 

 tinual action when the earth's crust was perhaps 

 thinner than now, would speedily pour out masses 

 of material extensive enough to alter the level of 

 the ocean bed, and cause its waters to drain off 

 to other parts of the land. Extraordinary changes 

 in the distribution of land and sea have taken 

 place within historic times, and even during our 

 own lifetime, from the same or similar causes." 



FlO. 16. Trilobite (Phacops caudatus). 



When we had been at work for another hour, 

 Baxter suddenly cried out, " What in the world is 

 this ? I think I have discovered something at last." 

 Taking the piece of limestone from his hand, and 

 looking at it, I saw at once he had managed to 

 knock out of the rock with his rude hammer of 

 stone a very valuable fossil. 



" Well, you are a lucky dog," I said. " You have 

 actually got the greater part of a trilobite ; the 

 Fates evidently intend you to be a geologist." 



