WATER IN FOUNDATIONS. 



89 



of a hemispherical shell 3 feet in diameter at the base, with a 

 circular opening 6 inches in diameter at the top continued in 

 the form of a pipe terminating in a flange, to which 6-inch pipes 

 could be bolted, room bsing left for the nuts between the lower 



Concrete 



FIG. 59 



surface of the flange and the shell (Figs. 59, 60). As the excava- 

 tion was proceeded with in the neighbourhood of the boil within 

 the stank formed by the planking, the flow of water and the 

 quantity of sand increased very much, and it was necessary 

 to keep two chain- pumps 

 at work to remove the 

 water. A 9-foot length 

 of 6-inch pipe, bolted 

 to one of the castings 

 just described, was then 

 lowered into the funnel- 

 shaped cavity (Fig. 59), 

 from which the water 

 flowed ; the casting sank 

 until the top of the pipe 

 was just level with the 

 water. The space within 

 the planking was half 

 filled with concrete to 

 within 1 foot of the top 

 of the pipe. If the dia- 

 meter of the pipe had been larger, the whole of the water 

 would probably have flowed up it, and the concrete would have 

 been sound ; as it was, the pipe could not take all the water, 

 which at one time rose in a jet 2 feet high, and much water 



FIG. 60. 



