CLAYS OF MIDDLESEX COUNTY. 443 



Chemical analysis of a ball clay. W. H. Cutter, Woodbridge. 



Razv. Burned. 



Silica (SiO.), 45-76 53-33 



Alumina ( A1 2 3 ) , 39-05 45-51 



Ferric oxide (Fe^Os) , trace .... 



Lime (CaO), 0.95 1.10 



Magnesia (MgO), 0.04 0.05 



Alkalies (Na 2 0, K-0), trace 



Loss ignition (chiefly H 2 0) , 1446 .... 



100.26 99-99 



This is lower in fluxing impurities than the No. 1 fire clay from 

 the same district, and it is difficult to see just what should cause 

 the color in burning-. 



Other analyses. — The following analyses o>f highly refractory 

 clays from the Woodbridge district are given by Prof. Cook, in 

 the Report on Clays for 1878 (p. 51) : 



Analyses of highly refractory clays. 



123 



Alumina (AI2O3), 40.14 37.94 38.87 



Silicic acid (combined),... 42.88 44.26 44-77 



Water (PLO), 13-59 14.10 12.97 



Quartz sand, 0.50 1.10 0.80 



Ferric oxide (Fe20 3 ), .... 0.51 0.96 1.14 



Magnesia (MgO), o.n 0.11 



Lime (CaO), 0.10 .... .... 



Potash (K2O), 0.41 0.15 0.16 



Soda (Na 2 0), 0.08 



Titanium oxide (Ti0 2 ),... 1.42 1.30 1.30 



Totals, 99-63 99-92 100.12 99-99 



i. Loughridge & Powers' fire clay, Woodbridge. 



2. Hampton Cutter & Son's fire-brick clay, Woodbridge. 



3. Hampton Cutter & Son's ware clay, Woodbridge. 



4. A. Hall & Son's fire clay, Woodbridge. 



5. Wm. H. P. Benton's fire clay, Woodbridge. 



4 



5 



36.49 



37-92 



42.82 



42.40 



12.42 



14.60 



5.80 



1.41 



0.78 



1.05 



O.II 





0.45 



35 





0-37 



1. 12 



1.41 



