WASHING AND GRADING SAND FOR CONCRETE. XIX, 
results may be of some use to members, the author has 
included them in the paper. The instructions given, and 
the results obtained, are tabulated below. 
TESTS OF VOIDS IN BROKEN METAL. 
Crown-street Depot, 27/8/01. 
Material for Tests.—Bluestone metal to be of a size 
to pass freely, with its largest dimension, through a ring 
14 inches diameter, and screened through a_ sieve of 
meshes 4 inch apart. Sandstone metal to be of a size 
to pass freely, with its largest dimension, through a ring 
2 inches diameter, and screened through a sieve of meshes _ 
+ inch apart. 
Method of Testing.—Hach test shail be made three 
times in succession, and the mean of the three tests shall 
be considered correct. 
1. Fill gauge with 15 inch metal, then fill with water 
accurately measured. . 
. Fill gauge with 2 inch metal, then fill with water 
accurately measured. 
bo 
3. Mix 80% of 2 inch metal with 20; of 14 inch metal. 
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da 95 00% 59 2 ae a 40 4a 38S “o 
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In each case place the metal in gauge and fill with 
water, accurately measuring the same. 
8. Mix as much sand as possible with the gauged quantity 
of 2 inch metal, without increasing its bulk. 
9. Mix as much sand as possible with the gauged quantity 
of 15 inch metal, without increasing its bulk. 
10. Mix as much sand as possible with 50% of 2 in. and 50% 
of 15 inch, without increasing its bulk. 
11. Interstitial space in sand used. 
Gauge box for metal measured 4 ft.,x 4ft. x 1ft. 6in. 
Gauge box for sand measured 1ft. x 1ft. x 1ft. 
