Haworrt. | Detailed Geology. 97 
regarding the influence of local rains. The writer has been 
acquainted intimately with this mining district ever since 
-Iining first began at Joplin in 1870 and 1871. From per- 
sonal observation many instances are known wherein there 
was a complete abandonment of mining operations on ac- 
count of heavy rain storms. One remarkable instance was 
in the year 1885. A period of unusual rain storms prevailed 
for some weeks, during which time a tornado destroyed a 
large part of the business center of Oronogo. The rains were 
of the torrential kind commonly accompanying severe wind- 
storm periods. Almost every mine at Webb City and Car- 
tersville, many of the mines at Joplin and fully half of them 
at Galena were shut down on account of mine water, some 
of them for three or four weeks’ time. A portion of this 
water ran into the mines from the surface drainage, hut long 
after the mines were first unwatered the supply of ground 
water continued unusually great, and seriously interfered 
with mining operations. 
Here and there throughout the entire district are certain 
areas which are protected by an unusually tight roof so that 
local rains apparently have little influence. An inquiry 
made from operators of such mines doubtless would bring an 
answer that local rains had but little influence. Quite possi- 
bly the same inquiry might be made of an operator within a 
mile of the first mine and the answer would be just the 
reverse. | 
An attempt was made to investigate the source of ground 
water in a somewhat positive manner. For this purpose two 
well-known mining areas at Galena were chosen, the Mastin 
land southwest of Galena, and the South Side Mining Com- 
pany’s land on the east. The Mastin land lies in a sort of 
valley, with low hills on almost all sides of it. From the 
north end water drains to the northwest into Short creek, 
and from the south end it drains southward into Shoal creek. 
Mr. Charles McClaire was assigned the task of estimating 
the amount of water pumped from the mines, the drainage 
area, and probable return of water from the mines. The 
Mastin valley nas surface water draining into it from about 
(—viil 
