46 KINDLE 



The roof, thus weakened, gradually dropped down. This would account 

 for the rumblings and mysterious noises noticed by the tenants of the 

 Todd house for some time before the cave-in. Then, with his large pump, 

 Smith drew that water off suddenly, and the roof gave away. Since that 

 time the 35 gallons has been running into the Todd hole and this inflow 

 and sudden evacuation caused the trouble. 



I have endeavored to recall all of the circumstances and incidents 

 connected with the trouble and nothing presents itself to me which nega- 

 tives this theory, except one possible incident: 



At the Clem Ice Factory, in the Valley 600 or 800 feet north of the school 

 house, there are four shallow wells, ranging from 16 feet to 20 feet in 

 depth. On the night following the slump, the pump in the deepest well 

 failed to catch the water for an hour or one and a half hours. The same 

 thing occurred the following night. Mr. Clem does not know whether 

 or not any of the other walls were affected. I cannot attach great im- 

 portance to this incident. The water was low for only i-^ hours at most 

 and that may have been because he was drawing harder at that par- 

 ticular point. The fact that he dug four wells and uses them all tends to 

 show that one of them could easily be temporarily exhausted." 



As previously pointed out by Van Horn 8 the data given by Mr. 

 Yost seem to establish clearly the fact of direct connection between 

 the stream tapped at 790 feet by the deep well and the water in 

 the cavern under the "cave-in." 



But the vital question in any interpretation of this relationship 

 in explaining the caving is, did the water enter a previously empty 

 cavern through the agency of the Soo-foot well, as Mr. Yost sup- 

 poses, or did pumping the well empty the cavern which was previously 

 full and which had never before been drained ? It is the writer's 

 view that the latter supposition is much the more probable. This 

 probability is indicated by the fact that when the pumping ceased, 

 which was utilized to lower the water in the "cave-ins" during the 

 process of arching with cement the openings in the streets, and at 

 the Todd house the water rose nearly to the surface in hole No. 3. 

 The rise was very rapid, 3 to 4 feet per hour, or about 35 gal- 

 lons per minute, till it stood within 10 feet of the surface. 

 Above this point the rise was very much slower, about 5 to 6 

 feet per day, until it reached within 5 or 6 feet of the surface. 

 "it was still rising at about this rate when pumping was resumed, 

 and has since continued." (Letter from J. Yost, April 22.) 

 If this water had entered the "cave-in" through the deep 



8 Mining and Engineering News; Sept. i, 1910. 



