10 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1926 
found beneath. The work of preparing this exhibit consisted, therefore, of 
removing the overburden of loose dirt and broken rock, then quarrying off the 
loose upper laminae until a solid and continuous face covered with footprints 
was reached. This was done, and a smooth surface 8 feet wide and 25 feet 
long was carefully uncovered. 
At the side of the slab leading up from the trail a series of stone steps was 
laid in order to facilitate examination by those interested in the footprints 
eovering its surface. Although this slab constituted the main exhibit, other 
large surfaces were similarly uncovered, so that in all there are several hun- 
dred square feet of rock surface showing imprints of feet, thus forming a 
permanent exhibit of the various tracks and trails to be found here. 
The great antiquity of these footprints is clearly demonstrated at this locality, 
for it is evident that since the day when those animals impressed their feet in 
what at that time was moist sand more than 1,000 feet of rock-making ma- 
terials were piled up in successive strata above them, and this does not take 
into account many hundreds of feet more that have been eroded off the present 
top of the canyon wall. 
The great length of time necessary for the cutting away or erosion of the 
rock to form the deep canyon and the even longer time necessary for the 
original deposition of this great vertical mass of stone when translated into 
terms of years, if that were possible, would be so stupendous as to be almost 
beyond human comprehension. 
BIOLOGICAL COLLECTING IN WESTERN CHINA 
The collecting of biological material for the National Museum was 
coutinued in the Province of Szechwan, western China, by the Rev. 
David C. Graham. Various trips which he had proposed to take 
had to be abandoned because of the presence of numerous bandits in 
certain areas, and his work was greatly handicapped by civil-war 
conditions in that part of China. Nevertheless, Mr. Graham suc- 
ceeded in making large collections of valuable biological material 
for the Museum. 
While still undecided as to his summer’s plans for collecting, Mr, 
Graham received notification that all foreigners were requested to ga 
together to Kiating, with a heavy military escort for safety. Re- 
garding his activities after this, a brief account prepared from 
Mr. Graham’s letters reads in part as follows: 
The party reached Kiating on July 7, and having gone thus far, Mr. Graham 
decided to try for Washan Mountain, and had actually started, when on the 
12th a messenger arrived with a letter saying conditions were getting worse 
down the river, that many British subjects were leaving Szechwan, and that 
all foreigners might be ordered to leave, also advising that he abandon his 
plan to visit Washan. He notes: “It is a keen disappointment, but it seems 
unwise to go on, so to-morrow I’ll go back toward Mount Omei and spend the 
summer as profitably as I can.” On July 14 he received a letter stating that 
conditions were improving and that the foreign community withdrew its request 
that he should not attempt the trip to Washan. He thereupon again headed 
for that mountain, and on July 23 reached the summit, which he says is the 
highest point in central Szechwan. On every side “it is a sheer cliff several 
thousand feet high, with only one road to the top and back * * * The road 
