GENERAL ENGINEERING DATA OOO 



Pies and Posen 5 cite a crushed quartz rock used for molding sand 

 which, with a specific gravity of 2.52, has a porosity of 30.6, which would 

 mean 1,770 ounces per cubic foot. 



From Trautwine we find that a cubic yard will swell to 1.75 cubic 

 yards when broken in fragments, and that anthracite, which weighs some- 

 thing like 1,500 ounces to a cubic foot solid, will run to something like 

 800 to 1,000 ounces to a cubic foot in our cellar. Dry potters' clay will 

 be something like 1,800 to 2,100 ounces per cubic foot. Sand will be 

 something like 1,410 to 1,700 ounces per cubic foot. The more evenly 

 sized it is, the lower will be the weight. With sea sand, even with thor- 

 ough settling, there were 32 per cent of voids and the weight was 1,792 

 ounces per cubic foot. Wet sand, however, will weigh 1,856 to 2,064 

 ounces per cubic foot. 



Peelers Handbook reports, page 119, that clay settling in water had 

 50 to 79 per cent of voids; that pebbles had 44 per cent of voids when 

 loose and 39 per cent when watered and rammed. Dry sand weighed 

 1,600; wet, 1,952; dry gravel, 1,793; wet, 2,000 ounces per cubic foot. 

 Dry clay might be as light as 1,020 ounces per cubic foot when loose, but 

 1,857 in place, or 2,082 if compressed. In hard broken rock voids were 

 35 per cent when all sizes were mixed and shaken, but if screened to even 

 size voids rose to 45 to 48 per cent, and, generally speaking, 1 cubic yard 

 cut corresponds to 1.4 cubic yards filled. 



A. Gr. Webster 6 found that a sand which, when screened, gave between 

 the sizes below (a) the percentages below (b), showed no excess of water 

 when mixed with 25.9 per cent (3.5 pounds of water to one of sand), but 

 a slight excess with 3.75 pounds — that is, 27.3 per cent. 



(a) .2 to .073, — to .034, — to .022, — to .011, — to .0055, — to .0029 inch 



(b) .05 .1 .4 4.85 55.05 22.25 



are the percentages retained between these diameters — that is, more than 

 half between .011 and .0055 inch. With the excess water the anpde of 

 repose was 14°. 5. 



Henry Mace Payne, in discussing Yukon mining, 7 reports the weights 

 of certain frozen material: Black and sandy muck, 1,401 ounces a cubic 

 foot; gravel and sand rock, 2,189 ounces a cubic foot; bedrock, 2,590 

 ounces a cubic foot. 



A. F. Melcher, 9 using the paraffin dip method on oil "sands," as cited 

 below, has given many observations on their porosity and mineral specific 



5 Michigan Geological Survey, 1907, p. 52. 



6 Proc. Nat. Acad. Sci., July, 1919, p. 263. 



7 Transactions Canadian Mining Institute, vol. xvi, 1913, p. 23G. 



