WATER IN FOUNDATIONS. 93 



of the clay proving irregular, and, as the overlying fine red silt 

 was for the most part hard and compact when undisturbed, 

 the walls were founded upon it at a general depth of 9 or 10 

 feet below the dock bottom. In places, however, where the 

 foundations were bad, the walls were founded at a lower 

 level. 



These foundations, although they were firm and compact 

 when left quiet, quickly became very unstable if disturbed 

 or chafed in any way ; they therefore required careful treatment. 

 Springs were of frequent occurrence and were dealt with 

 according to circumstances ; but in a general way they were 

 allowed perfect freedom until the surrounding area of founda- 

 tion had been made secure, after which they were choked by 

 concrete deposited in mass. In dealing with a spring, concrete 

 was prepared in sufficient quantity upon a platform immediately 

 above it, and, on word being given, it was deposited as quickly 

 as possible, the operation being performed in the course of a 

 minute or two. When the springs carried sand with them 

 which was often the case stable litter was freely used, and 

 weighted down so as to filter the water and hold back the 

 sand. 



In the foundations of the passage leading from the Fleet- 

 wood Dock to the timber pond, numerous springs caused a good 

 deal of trouble ; they threw up large quantities of sand, which 

 it was difficult to check. No attempt was made to stop these 

 springs, but the passage of sand was checked by using straw 

 and stable litter so as to filter the water and keep back the 

 sand. 



The foundation was divided into sections or compartments 

 of from 6 to 8 feet square, formed by close boarding driven 

 12 inches into the bottom, the object being to prevent the sand 

 washing out from beneath the concrete when deposited, and 

 to secure the latter against the wash of the water. Sufficient 

 concrete was prepared to fill each compartment to a height of 

 3 or 4 feet; when all was ready, this was quickly deposited 

 almost as one mass, whereupon the spring, taking the line 

 of least resistance, immediately appeared in an adjoining 

 compartment only to receive similar treatment. The springs 

 were in this manner driven to the corner or point first decided 

 upon, and, when the floor had been further strengthened by the 

 addition of concrete, they were smothered without difficulty 



