524 Scientific Geology. 



course slightly to reach Newport R. Island. Above sections B & C, a 

 few short sections are introduced of interesting" places lying too far north 

 of the line of the general sections to be made part of them. In these 

 minor sections the same scales are employed as in the larger ones. 



The horizontal scale used in all these sections corresponds with that 

 on the Geological Map : so that the sections are of exactly the same 

 length as the Map, measured on the dotted lines above described. 

 Hence any particular spot on the section may be found upon the State 

 Map, by laying the one upon the other. The scale for laying off the 

 heights is 1500 feet to the inch. 1 do not suppose that I have always 

 given the height of the surface with much exactness. I have depen- 

 ded on several surveys that have deen executed within a few years for 

 contemplated canals and railways, and on other admeasurements pub- 

 lished by individuals, for the heights of the most important points 

 along the sections. But in some instances the course of these surveys 

 did not correspond with the line of the sections. In such case I could 

 only approximate to the elevation. 



The double scale necessarily employed in extensive sections of this 

 kind, gives so distorted a representation of the surface, and consequent- 

 ly of the relative situation of the different rocks, as exceedingly to di. 

 minish the value of such representations. Geologists accordingly at 

 the present day place but little dependance upon them : or rather they 

 value them less just in proportion to their distortion. "Such sections," 

 says De la Beche, "are little better than caricatures of nature, and are 

 frequently much more mischievous than useful, even leading those 

 who make them, to false conclusions, from the distortion and false 

 proportions of the various parts."* If to this it be added that there 

 is a strong temptation to make up for a deficiency of observation by 

 giving the relative position of the rocks according to a favorite theo- 

 ry, we shall be persuaded that a large part of the sections hitherto 

 published, have conveyed to the mind nearly as much error as truth. 

 A section which exhibits only the truth, so far as the observer has as- 

 certained it from actual examination, forms too naked and uninviting a 

 sketch to satisfy the taste or the ambition of many. Hence the imag- 

 ination and the painter are taxed to make up the deficiency. 



In the sections appended to this report, however, I have endeavor- 

 ed to present the dip and superposition of the rocks, only so far as I 

 have determined these points from actual observation. Where for in- 



♦Geolog-ical Manual 2d Edition p. 545. 



