34 COLORADO COLLEGE STUDIES. 



SarcopJiagus cave, at the Natural bridge on Bear creek, south 

 of Sun City. This cave has been opened along t^vo 

 master-joints which intersect at an angle of about 70 de- 

 grees, and it accordingly has two entrances, one about five 

 rods south, the other immediately north of the Natural 

 bridge, and neither far above the bed of the creek. In 

 cross -section, and as well seen at the north entrance, the 

 cave has nearly the form of an upright sarcophagus, widen- 

 ing gradually upward to a shoulder-region of maximum 

 breadth, contracting suddenly above the shoulder to a 

 crested head-part, and narrowing to a simple fissure both 

 above and below. The present open portion of the cave 

 extends only from the two entrances to the intersection of 

 the joint-planes, distances of about 55 and 180 feet from 

 the north and south entrances respectively; but both gal- 

 leries formerly extended in to an unknown distance beyond 

 this point, the continuation being now filled with compact 

 cave-earth. It seems probable that the entire cave was 

 once so filled and that the portion now open was subse- 

 qaently re-excavated by the water of Bear creek, a portion 

 of which is diverted from the main channel and traverses 

 the cave during ordinary freshets. The north gallery has 

 also an outward extension of its roof for 11 feet in the over- 

 hanging wall at its entrance, the lower part of the gypsum 

 having been here cut away and the cave thus much short- 

 ened by the creek's erosion. The breadth of the "Sar- 

 cophagus," across shoulders, in this gallery is 4 feet and 8 

 inches at the entrance, gradually increasing in the inner 

 half to 7 feet near the junction of the galleries. The height 

 of this gallery is over 9 feet above the narrow earth-floor 

 at its entrance and gradually diminishes inward. The south 

 gallery has a nearly uniform breadth of 4 feet and 6 inches 

 across shoulders and, containing more earth than the 

 north gallery, has a broader floor and a height only about 

 equal to its breadth. 



A fine example of an arch-cave is seen on Cave creek. 



