206 



ANNALS NEW YORK ACADEMY OF SCIENCES 



25 pounds for a period of 11 months. Parallel specimens were stored in 

 damp sand during this period and allowed to attain their full normal 

 strength. The table following shows the leakage and final strength of 

 the specimens: 



TABLE 15 



Percolation through Concrete Specimens 



TABLE 16 

 Comparison of Strength before and after Permeability Test 



7 One specimen crushed. Other results are average of two specimens. 



Effect of the direction of flow through concrete. Concrete seems to 

 offer less resistance to the flow of water when the direction of the flow is 

 parallel to the bed than when at right angles to it. A test covering this 

 point was made with 8-inch cubes of concrete of the proportions 1:4:14, 

 fine and coarse aggregate being a standard crushed Milestone. 



