476 GEOLOGICAL EXCURSION TO THE ROCK* MOUNTAINS. 



iMU&i 



Wales or the dbris along t lit- V"6zere in Mesozoic rocks. As in the 

 cliff of Dordogne, so in the Walnut canyon, these shelters have been 



occupied by people whom (lie necessities of 

 primeval life or the exigencies of war drove 

 to easily defended fastnesses in the rocks. 

 They do not imply that the races who 

 availed themselves of these strongholds 

 were in a more rude stage than those who 

 lived in hutB upon the plateau. In the Mid- 

 dle A.gesrthe bock of Tayac was long held 

 by the English, and so the remains left by 

 the Indian tribe which occupied these cliff 

 dwellings in the Walnut canyon did not 

 lead us to infer that it was in an early stage 

 of civilization. The fragments of pottery 



FIG. 80. — Section in Walnut canyon. ' ■ 



showed much artistic taste and skill. The 



stone arrowheads were highly finished and of the same type as those 

 used by the Indians of historic time. The walls of the dwellings were 

 of stone cemented by mortar, in which were pieces of pottery, Showing 

 that the building was still going on after the tribes had lived there 

 for some time and scattered household rubbish about. Cobs of In 

 dian corn told of cultivation, while their state of preservation con- 

 firmed the impression, derived from the mortar and other remains, 

 thatrthere was no ground for assigning the occupation of the cliff to any 

 remote antiquity. 



SECTION IN CONGRESS CANYON OPPOSITE POINT SUBLIME. 



By Dr. PbITZ Fkkcii. 



The succession of strata exposed in the (hand Canyon of the Colo- 

 rado has already been several times described («aB.«). 



But all the sections hitherto published differ somewhat in regard to 

 the petrographical character, the relative thickness and the disturb- 

 ances of the strata, and as the section shown in Congress canyon has 

 not been investigated before by any geologist, it may well be described 

 at some length. The section is interesting not alone for the opportu- 

 nity it affords to make a diagnosis of the petrographical character of 

 the strata. There are probably few places on theearth where the geo- 

 logical phenomena of folding, faulting, uplifting, as well as numerous 

 transgressions, may be so easily taken in at a single glance. 



As the geologist passes upward from the bottom of the canyon to 

 liance's cabin he crosses the terraues of the following principal geolog- 



