202 RESEARCH IN CHINA. 
whence it flows, chiefly in similar material, southward, underground. Its 
source may be in the vicinity of the Sha-ho. 
Inquiries regarding the annual rainfall at Peking have not met satisfac- 
tory answers. It appears to be irregular in amount, there being extremes 
of wet and of drought. Dr. N. S. Hopkins, of the Methodist Mission, 
stated that measurements at a station some distance northeast of Peking 
gave 56 inches one year and only about one-eighth of that amount the 
next. During wet years the ground becomes saturated. During the dry 
years it is to a greater or less extent emptied by evaporation and seepage. 
The deeper waters are, no doubt, more constant than those near the surface. 
There is good reason to believe that there is within reach of the people 
of Peking an adequate supply of wholesome water which may be reached 
by boring to moderate depth. 
