464 SMITHSONIAN MISCELLANEOUS COLLECTIONS [VOL. 50 



and partaking of the nature neither of a mountain nor butte. At 

 best, the elevation is but a low, circular ridge, and in the existing 

 condition of our knowledge might be well renamed Meteor Crater. 



External Appearance. — As seen from the railroad and other 

 points within a few miles, the crater rim rises above the level of the 

 plain in the form of a low hill with peculiarities of contour and 

 surface configuration that at once catch the eve of the observant 

 and serve to differentiate it from the surrounding mesas. Its ap- 

 pearance, as viewed from the northeast and from the south, is 

 shown in plate lxi. East and west views differ in detail, which, 

 though of importance in connection with the origin of the crater 

 itself, are not sufficiently conspicuous in the photographs to warrant 

 reproduction. 



A near view shows the mass of the crater rim (as the hill proves 

 to be) to be composed, so far as visible, of loose, unconsolidated 

 material in fragments of all sizes from microscopic dust to blocks 

 weighing hundreds of tons (pi. lxii). The jagged nature of the 

 ridge increases until the summit (pi. lxiii) is reached, where a 

 full view of the phenomenon and its surroundings is obtained (see 

 pi. lxiv, figs. 1 and 2) 1 . From this point it is seen that the crater 

 walls are composed of the crushed, broken, and bent strata of the 

 limestone and sandstone forming the floor of the surrounding- 

 plain (pi. lxv), and which dip away from it in all directions. In 

 other words, the structure is that which is known as quaquaversal. 

 The crater rim is at its highest point 160 feet above the plain, ac- 

 cording to Mr. Barringer, and at its lowest 120 feet. In outline 

 the crater is itself nearly circular, though showing numerous minor 

 deformations (see contour map, pi. lxvi). The diameter along an 

 east to west line is given as 3,808 feet ; along a north and south line 

 as 3,654 feet, 2 and the depth as approximately 600 feet from the 

 crest of the rim, though, as will be noted, this is considerably short 

 of the original depth. 



Details of Structure. — As already noted, the crater rim is com- 

 posed exteriorly, so far as exposed to view, of loosely consolidated 

 fragmental material, for the most part angular, and beyond ques- 



1 The view from this point, particularly about sundown or by moonlight, is 

 weird and impressive in the extreme. The inwardly steep and even overhang- 

 ing walls, profoundly shattered, surrounding on every side a broad, deep pit, 

 accessible only by the steepest of trails, barren of all but the scantiest of vege- 

 table life and gashed by torrential action, present a picture which, when one 

 reflects on its probable origin, is never to be forgotten. 



2 Later measurements by Mr. Lombard, of Flagstaff, give the major diameter 

 as 3,950 feet and the lesser 3,850 feet. 



