1893.] ESSAYS. Ill 



that made possible those accumulations of organic remains which 

 were compacted slowly into limestones and marbles. 



It is not my purpose to trace the history of the stages of changes 

 by which the earth has come to its present condition, but let me call 

 your attention to these facts. The crust of the earth cooled, then 

 oxidized and crumbled, the sea raked over the early gravels and re- 

 cemented them. In this way the stratified rocks were formed, and 

 were interleaved with deposits of limestone, and iron ore, and salt, and 

 coal, and from the re-pulverizing of these re-crystallized and massive 

 layers and the mixing of the organic with inorganic material we get 

 the basis of our present soils. Have you ever wondered why the 

 earth was so many millions of years getting ready for man ? I can- 

 not answer the question in full, but a clue to a partial solution may 

 be found in common processes in the arts. Take for example a piece 

 of crude pig-iron. It is coarsely crystalline, as you see by this piece 

 in my hand. It is not very strong. Re-melt it and, better, mix it at 

 the same time with iron from another ore-bed. The cast-iron pro- 

 duct is finer grained and stronger. Put it in a puddling furnace and 

 work it over — the more the better — and it is stronger and tougher 

 still. Or, refine it still further, and the steel that can be made from 

 it has a tensile strength of eighty tons where the crude pig had a 

 strength of only two or three tons per square inch, and is so fine in 

 grain that only a powerful microscope can resolve the crystalline par- 

 ticles. The primitive soil of the carboniferous age may have answered 

 for the coarse vegetation of that day, for ground pines, and horse-tails, 

 and ferns, but it was not yet fine enough and well enough mixed for 

 grapes and sugar-cane, roses and orchids. It was not yet good 

 enough for man. For him marble must be crystallized and com- 

 pacted, gold and silver and copper washed out and refined by perco- 

 lating waters, sapphires and rubies and diamonds moulded, shaped 

 and colored, and best of all the dull, dun-brown earth have its coat 

 of dusty fur combed to a marvellous fineness. 



To this end large portions of the surface have been repeatedly sub- 

 merged, and then have emerged, have been like a boy in a bath-tub, 

 ducked and then allowed to dry and breathe, have been shower- 

 bathed in addition weekly for ages and are dirty still. 



But most of this is ancient, far-off work, — necessary, but done 

 ages ago. What has been done for us? What is now doing? are the 

 questions you ask. Be patient. The oxidizing and repairing of the 

 surface of the globe and after the crust became fairly stable, its fur- 

 ther oxidizing went on till about 40,000 years ago when the loose soil 



