LX. 



W. E. COOK. 



in every way to the eye. One was tested in the usual way, as 

 previously described, the other was dried for two or three days in 

 the engine-room, then weighed whole, and immersed in water, 

 and again weighed after twenty-four hours and after forty-eight 

 hours. It was then tested to destruction by crushing. Pieces 

 were then selected, both large and small, thoroughly dried, and 

 tested in the usual way, with the following results : — 



Poeosity. 



Size 



No. of 



No. 1 PIPE. 



No. 2 PIPE. 



Large pieces. 



Small pieces. 



Whole. 



Large pieces 



Small pieces. 



in 



inches 



sets of 

 tests. 



Increase in 

 weight per 

 cent, after 



Increase in 

 weight per 

 cent, after 



Increase in 

 weight per 

 cent, after 



Increase in 

 weight per 

 cent, after 



Increase in 

 weight per 

 cent, after 



9 



14 



28 hrs. 

 2-46 



48 hrs. 



2-72 



28 hrs 

 2-50 



48 hrs. 

 2-61 



24 hrs. 



1-72 



48 hrs. 

 1-83 



24 hrs. 



48 hrs. 

 2-47 



24 hrs. 



48 hrs. 



2-30 



2-15 



230 



12 



9 



3-16 



3-39 



z-90 



3-00 



2-50 



2-69 



3-13 



3-17 



2-91 



3-14 



Average No. 1 Pipe, pieces, increase in weight after twenty-four 

 hours 2-69 per cent.; after forty-eight hours 2*87 per cent. No. 

 2 Pipe, pieces, increase in weight after twenty-four hours 2*54 per 

 cent.; after forty-eight hours 2-78 per cent.; whole, after twenty- 

 four hours 2*03 per cent.; after forty-eight hours 2-19 per cent. 



The foregoing results cannot be taken as absolutely conclusive, 

 as in some cases the crushing strain of the second pipe was greater 

 than that of the first pipe. Taking the average result as approxi- 

 mately correct, it is found that a pipe saturated with water loses 

 8 per cent, of its original strength against crushing. 



The only other cities in Australasia where sewerage works are 

 in progress, or have been recently carried out, are Melbourne, 

 Adelaide, and Wellington (N.Z.) 



Melbourne. — The Melbourne limit for permeability after twenty- 

 four hours immersion of the whole pipe, is 4 per cent. A table is 

 given, showing the average results of a number of tests in 

 Melbourne : — 



Diameter. Thickness. Weight Weight after Cross breaking 



Inches'. Inches. Dry. 24 hours in water. 18-inch centres. 



24 1J 288 289 3,800 



18 1J 186 196£ 3,360 



