12 BUREAU OF AMERICAN ETHNOLOGY [bull. 66 



Professor Bowman's report gives geologic details and contains a 

 number of interesting conclusions, which illustrate, in view of knowl- 

 edge acquired later, how easy it is sometimes even for a specialist 

 to be in error. He summarizes the results of his study of the case 

 as follows: 



The bones found near Cuzco were ronlemjiofaneous with the compact gravels 

 in whieli tliey were embedded. They were disposed in the form of a lense 

 about 10 feet lonj; and 6 inches tliick. From (1) theii* disposition with respect 

 to each otlier, (2) their rehitions with the bedding ])lanes, and (3) their worn 

 condition, it is concluded that they were interstratlfied with the gravel beds. 

 The age of the beds thus becomes the critical factor in the interpretation. 

 From a detailed study of the geology of the upper Cuzco basin with special 

 reference to glacial forms, it is concluded (1) that the beds belong to a 

 glacial series, (2) that the bones were deposited during a period of pronounced 

 alluviation. and (3) that since the deposition of the bones from 75 to 150 feet 

 of gravel were deposited over them and later partly eroded. The age of the 

 vertebrate reniains may be provisionally estimated at 20.000 to 40,000 years. 



It is only fair to state that in the following paragraph of his 

 report Professor Bowman points to weaknesses of the case — that 

 there is a lack of sharp distinction between certain of the bones 

 found with the human remains and referred to the bison, and the 

 bones of modern cattle ; that " certain canine bones gathered in con- 

 nection with the human remains can not be said to be unlike those of 

 the modern domesticated dog " ; and that there is a fair possibility 

 "■ that the bluff in which the bones were found may be faced by 

 younger gravel, and that the bones were found in a gravel veneer 

 deposited during later periods of partial valley filling." 



Farther on in Professor Bowman's report some of the above points 

 are accentuated : 



The relation of the bones to the surface of the blutf leads to some important 

 considerations. The finding of material on the immediate face of the bluff 

 does not merely by virtue of that position indicate with certainty natural burial 

 during the upbuilding of the formation and reexposure as a result of present 

 erosion. Though the bluff is very steep, a number of plant forms cling to it. 

 These catch particles of falling or sliding material and even pieces of pottery. 

 In a number of cases it was noted that the vegetation responsible for such 

 obstruction in time dies, and may be entirely or almost entirely removed. Sur- 

 ficial objects are then left attached to the face of the bluff, from which they 

 may be easily removed. The steeper the bluff the more difficult the retention 

 on a sloping sui-face becomes. The patchy mantle of foreign material is 

 always loose, unstratified, fine textured, and in strong contrast to the undis- 

 turbed material directly beneath it. As contrasted to such surface drift, it 

 is noteworthy that the vertebrate remains were not on the face of the bluff, 

 but 8 inches back from the face, measuring to the median line of the deposits; 

 also that they were stratified with the gravels, mixed with material of about 

 the salne texture and composition, and that they lay in a nearly horizontal 

 plane. 



