CLAYS OF NEW YOKK 



559 



The silica used in tlie experiments was qnartz, ground to pass 

 a 100 mesh sieve and purified by boiling in nitro-bydrocbloric acid. 

 It bad 99.88^ silica. The alumina contained 98.48 Al Og. 



The method followed was to weigh out samples of 1 gram of the 

 clay to be tested and mix them severally with .1, .2, .3, etc., 

 grams of the silica-alumina mixture. The samples were then tested 

 in the Deville furnace. 



The following table gives the results of the experiments just de- 

 scribed, the clays being arranged in the order of their refractoriness, 

 and in each case the amount of flux being given that was required 

 to raise the fusing point to that of cone 26 of Seger. 



Analyses and results of tests. 



Sample no. 



26« 



SS't 



3a 



22" 



24a 



23a 



1982& 



SiOa 



AlA 



HgO comb . . . 



Per 



cent 



64.10 



21. T9 



6.05 



Per 



cent 

 55.60 

 24.34 



6.75 



Per 



cent 



57.10 



21.29 



6.00 



Per 



cent 

 57.45 



21.06 

 5.90 



Per 

 cent 



57.15 



20.26 

 5.50 



Per 

 cent 



49.30 



24.00 

 9.40 



Per 



cent 

 43.94^ 

 11.17 



3.90 



Total 



91.94 



86.69 



84.39 



84.41 



82.91 



82.70 



59.01 



F2O3 



CaO 



MgO 



K2O. 



2.51 

 0.10 



0.58 

 2.62 

 0.03 



6.11 

 0.43 



0.77 

 3.00 

 ('.09 



7.31 

 0.29 

 1.53 

 3.44 

 0.61 



7.54 

 0.29 

 1.22 

 3.27 

 0.39 



7.54 

 0.90 

 1.62 



3.05 



0.58 



8.40 

 0.56 

 1.60 

 3.91 



0. 7 



3.81 



11.64 

 4.I7 



2.9o 



0.7 



Nsi^O 



Total 



5.84 



10.40 



13.18 



12.71 



13.69 



14.63 



23.23 



Moisture .... 



1.10 



2.65 



, 1.30 



1.90 



2.70 



1.20 



15. 66« 



Grand total. . 



98.88 



99.74 



98.87 



99.02 



99.30 



98.54 



98. OO'^ 



Stiffening in- 

 gredient, p.c. 



20 



40 



60 



80 



80 



100 



180 



« Analyzed by N. W. Lord. 

 c Includes C02- 



^ Analyzed by E. Orton jr. 

 ^ Includes P205, 0.1 Oi«. 



