154 A CENTURY OF SCIENCE 



and Liebnitz, the cosmogonists de Maillet and Buffon 

 had been less instrumental in developing science than in 

 fitting a few facts and many speculations to their systems 

 of philosophy. By the opening of the nineteenth cen- 

 tury, however, men of learning were coming to appre- 

 ciate that the way to advance science was to experiment 

 and observe, to collect facts and discourage unfounded 

 speculation. Silliman's insight into the needs of geologic 

 science is shown in the following quotation (1, pp. 6, 

 7, 1818) : 



' ' Our geology, also, presents a most interesting field of inquiry. 

 A grand outline has recently been drawn by Mr. Maclure, with 

 a masterly hand, and with a vast extent of personal observation 

 and labour : but to fill up the detail, both observation and labour 

 still more extensive are demanded; nor can the object be 

 effected, till more good geologists are formed, and distributed 

 over our extensive territory. 



To account for the formation and changes of our globe, by 

 excursions of the imagination, often splendid and imposing, but 

 usually visionary, and almost always baseless, was, till within 

 half a century, the business of geological speculations ; but this 

 research has now assumed a more sober character; the science 

 of geology has been reared upon numerous and accurate obser- 

 vations of facts; and standing thus upon the basis of induc- 

 tion, it is entitled to a rank among those sciences which Lord 

 Bacon's Philosophy has contributed to create. Geological 

 researches are now prosecuted by actually exploring the struc- 

 ture and arrangement of districts, countries, and continents. 

 The obliquity of the strata of most rocks, causing their edges 

 to project in many places above the surface ; their exposure, in 

 other instances on the sides or tops of hills and mountains; 

 or, in consequence of the intersection of their strata, by roads, 

 canals, and river-courses, or by the wearing of the ocean; or 

 their direct perforation, by the shafts of mines ; all these causes, 

 and others, afford extensive means of reading the interior 

 structure of the globe. 



The outlines of American geology appear to be particularly 

 grand, simple, and instructive ; and a knowledge of the import- 

 ant facts, and general principles of this science, is of vast prac- 

 tical use, as regards the interests of agriculture, and the research 

 for useful minerals. Geological and mineralogical descriptions, 

 and maps of particular states and districts, are very much 

 needed in the United States; and to excite a spirit to furnish 

 them will form one leading object of this Journal. " 



