ee) hry 
SRE ge 

Uprrer: Fic. 51. A Ponp IN CoLorapo, PHOTOGRAPHED OcTOBER 8, 1913 
Lower: Fig. 52. THE Same Piacr, Octoper 18, 1922. Atui TRACES OF 
A Ponp Have DISAPPEARED. THE CHANGE REALLY TOOK 
PLACE IN Two YEARS 
101 
