Plate 5 



1, Air view, looking approximately west-northwest, the foreground in Sec. 4, T. 



5 N., R. 16 E. The small drainage basin in the foreground is on the Upper 

 Lebo (Fort Union No. 2). The Silberling Quarry is in the upper part of 

 the main right (northwest) branch of the coulee. The sparse timber marks 

 the basal Melville (No. 3) sandstone and the top of Bear Butte, which here, 

 near the middle of its length, is at its narrowest point. Beyond this is the 

 valley of Widdecombe Creek, hidden by Bear Butte, and beyond this, dim 

 in the photograph, rise low hills, without timlaer, developed on the Lower 

 Lebo (No. 1) along the axis of the Widdecombe Creek anticline. 



2, Site of the Silberling Quarry, looking approximately north in Sec. 4, T. 5 N., 



R. 16 E. The two figures near the middle of the picture stand near the 

 ends of the main section of the quarry. The slope is on the uppermost 

 part of the Lebo (upper No. 2), but the basal Melville (No. 3) lies immedi- 

 ately above, and numerous talus blocks from it are seen. The quarry is 

 not discernible as such, since the picture was taken in 1932, 24 years after 

 intensive work there. 



