THE SCENERY OF THE COAL PERIOD. 149 



CHAPTER XIV. 



THE SCENERY OF THE COAL PERIOD. 



TT was in the middle ages of the history of the world. 

 -^- The growing continents had lifted their brows above 

 the surface of the all-embracing sea ; but their spreading 

 plains and long-extended shores were still the empire of 

 the garpikes, and the nursery of illimitable beds of encri- 

 nites and polyps. The Gulf of Mexico jutted northward to 

 Middle Iowa, and rolled its widening waters northwest far 

 toward the sources of the Missouri River. There are good 

 reasons for believing that it stretched through the entire 

 length of the continent to the Frozen Ocean. The shore 

 line of the Atlantic reached from Connecticut through 

 Southern New York and Northern Ohio, Indiana, and Illi 

 nois, to the valley of the future Mississippi. All the centre 

 of Michigan was a sea-bottom, and not unlikely a gulf pro 

 jected northward over the peninsula now inclosed by the 

 great lakes. There was never, however, any free commu 

 nication between the Michigan Gulf and the ocean after 

 the later portion of the Devonian Age. Hudson s Bay 

 stretched far toward the site of Lake Superior, as the Arc 

 tic Sea pushed down from the north to fall into the warm 

 embrace of the waters of the Mexican Gulf. The great 

 lakes were not save, perhaps, Lake Superior nor the 

 mighty Mississippi, nor the thunder-voiced Niagara. The 

 youthful continent was yet unclothed with soil, save the 

 rocky detritus which nourished the lean vegetation which 

 began to garnish the land during the period of the Che- 

 mung and Marshall. The skeleton rocks protruded every 



