GEOLOGY. 219 



(two accompaiiied by folio atlases), tiftceu or sixteen octavo bulletins 

 (or monographs upon minor subjects), aiul two octavo volumes relating 

 to the mineral resources of the country. 



The U. S. Coast and Geodetic Survey was organized many years 

 since, for the purpose of accurately surveying the coast line and har- 

 bors of the country' and ascertaining and recording their changes, and 

 for tlie purpose also of connecting the coasts by transcontinental s^^s- 

 tems of triangulation, and so determining the elements of the geoid re- 

 lating to our domain. The surveys and maps of this institution are 

 immediately available as a basis for geologic investigations over the 

 areas which they cover ; and, moreover, the topographic and hydro- 

 graphic configuration of the coasts and harbors represents a condition 

 in the geologic evolution of the American coutineat, and so the inves- 

 tigations of the institution are in another way available to the geolo- 

 gist. Important contributions to geology annually result from the work 

 of the Coast and Geodetic Survey. 



The U. S. Signal OflBce is maintained for meteorologic observation 

 and prognostication, and observations are regularly made and recorded 

 over nearly all parts of the conntr3'. Now, climate (including the fall 

 of rain and the action of resulting rivers upon the surface of the earth) 

 is the most potent agency in geology ; and so the results of the Signal 

 Office are immediately available to the geologist, and some of the 

 notable contributions made to geological science during the biennial 

 period just closed have resulted indirectly from the operations of this 

 bureau. 



The Corps of Engineers of the U, S. Army is engaged in different lines 

 of investigation, some of which bear upon the action of rivers, the rel- 

 ative position of land and sea, and other geologic agencies and con- 

 ditions; and this Federal institution must accordingly be enumerated 

 among those whose operations annually result in geologic progress. 



Canada. — Second oidy to the U. S. Geological Survey in the magni- 

 tude and geographic extent of its operations is the Geological Survey 

 of Canada, which, under the directorship of Dr. A. R. C. Selwyn, has 

 been energetically prosecuted in various parts of the British dominion 

 on the American continent during the past two years. The Canadian 

 survey to day occupies very much the position occupied by the several 

 geologic and geographic surveys of the Federal Government during the 

 last generation, when an important function of the geologist was geo- 

 graphic exploration : to-day the Canadian geologist is (except when 

 employed in the relatively small portion of the Dominion now thickly 

 populated) pre-eminently an explorer; his journeys carry him over un- 

 known or little known tracts in the broad Saskatchewan plains, the 

 extended Hudson Bay region, and the inhospitable foot-hills and river 

 valleys of the northern Rocky Mountains; before he can satisfactorily 

 represent the results of his studies or even c()m])lete his field-work it is 

 necessary for him to map the tracts surveyed ; and eveu in the more 



