XX11 REPORT OF THE STATE GEOLOGIST. 



crepancies when used in the field. Especially is this the case in the 

 location and windings of streams. This is the natural consequence of 

 the character of work from which they are compiled, which is intended 

 to show only the position of streams with regard to survey lines. 

 This could be obviated by meandering and mapping the streams, pro- 

 vided there was no conflict in survey lines, but, unhappily, such is 

 not always the case. 



Besides these and the work now being done by this Survey in the 

 effort to prepare such maps as we need, based on accurate surveys, we 

 have the topography of twenty to twenty-four thousand square miles 

 (about one-twelfth of our entire area) in the center of the State, which 

 has been done under the United States Geological Survey. While 

 these maps are by far the best we have of this district, beautifully 

 executed and very useful indeed, it is nevertheless a fact that they have 

 proved so inaccurate in detail 'in many localities that we have been 

 compelled to add a topographic corps to that of the geologists proper, 

 wherever we have essayed to use them in anything like thorough work, 

 such as that in the Central Mineral Region. These United States topo- 

 graphic maps cover only a certain belt of country, and they do not 

 give us exactly the areas which are of most service to us. Thus the 

 sheets take in part of the Central Mineral Region, part of the Central 

 Coal Field, and part of the Eastern Cretaceous Belt ; and they are now 

 working eastward into a comparatively level country, in which, if any- 

 where, the geologist could manage to prosecute his studies without 

 them, leaving those portions of the regions mentioned where they are 

 most needed unfinished, and thereby increasing our work instead of 

 helping us. 



GEOLOGY. 



All geologic work heretofore done in Texas has been of such a dis- 

 connected character that we are unable to formulate any general results 

 from it, although many of the observations will be of great assistance 

 in working out the local geology. The several expeditions made along 

 the boundaries of the State and across it in various directions, were too 

 Hurried to give anything more than sketches of a few localities. Dr. 

 Ferdinand Roemer gave an excellent section of one district as he saw 

 it, and for his opportunities a remarkably comprehensive view of the 

 geology of the State, but this has subsequently been somewhat modi- 

 fied by other observers. Of the first State survey of Dr. Shumard we 



