HUMBOLDT'S FIRST BOOK. 19 



But as he was obstinate in "his theory he remained igno- 

 rant of this fact. He contended for the aqueous forma- 

 tion of almost every kind of rock, the Neptunic theory 

 as it was called, maintaining that even pumice stone was 

 the production of water. He would, not visit, however, 

 the volcanic districts of Italy, and the ancient volcanoes 

 of France, fearing perhaps that he might be led to aban- 

 don his first theory — a common fault of scientific men. 

 Still, considering the time in which he lived, and the 

 little that was then known of the true formation of the 

 earth, Werner was entitled to much credit, and is still 

 honorably mentioned as a pioneer in science. He raised 

 the art of mining into the science of geology. 



Such was Abraham Grottlob Werner, over whose mul- 

 tifarious writings Alexander was now poring. That 

 they made a deep impression on him may be gathered 

 from the fact that we find him, in company with his 

 friend Forster, in the spring of 1790, making a mineral- 

 ogical journey. Their route was to the Ehine, through 

 Holland, and to England. While in England Forster 

 introduced him to Sir Joseph Banks, the famous Presi- 

 dent of the Royal Society. Humboldt studied the rock- 

 formations of the countries through which he passed, 

 especially the basaltic rocks of the Rhine, and embodied 

 the result in a small work which was published in that 

 year. It was entitled, " Mineralogical Observations on 

 some Basaltic Formations of the Rhine," and was in- 

 tended to support the Neptunic theory of Werner. 

 Forster collected materials for his magnum opus, " The 

 Views of the Lower Rhine." In the meantime William, 

 who had returned from Paris, vibrated between Erfurt, 

 where he and the beautiful daughter of the president, 



