Proceedixgs of Seventeenth Xormal Institute 133 



The following statement of influence of fineness upon availa- 

 bility was agreed to by Messrs. Van Slyke, Fippin, Cavanaugh 

 and Collison: 



First. Availibility is approximately proportional to fineness. 



Second. Ten-mesh stone has about 50 per cent that will pass a 

 50-mesh sieve. 



Third. Use of ten-mesh size vs. fifty-mesh size depends on 

 quantity to be used and on cost of both material and of handling, 

 including freight. 



Fourth. About twice as much ten-mesh sieve as of fiftv-mesh 

 is required to furnish amount necessary for five year period or 

 average period of rotation. 



