140 DETAILED REPORT ON ALABAMA CLAT8. 



2200 P., the total shrinkage was 12 per cent., and the 

 bricklet white, with an absorption of 7.20 per cent. 

 At about 2250 F. the total shrinkage was 13 per cent, 

 and the bricklet, which had an absorption of 6.3 per 

 cent, was white with a very faint tinge of yellow. At 

 about 2300 F., the total shrinkage amounts to 15.5 

 per cent., the color of the bricklet white with a mere 

 shade ^f gray, and the absorption of it had decreased 

 to 1.3 per cent. The total shrinkage at about 2500 F. 

 was 17.5 per cent, and vitrification had occurred, the 

 bricklet being whitish in color. 



In the Deville furnace at cone 30, the form of the 

 clay pyramid was still erect, and while the clay was 

 thoroughly vitrified the angles were still sharp and 

 color whitish. The composition is : 



Analysis of Fire Clay, Rock Run, Cherokee Co. (No. 3). 



Silica 72.20 



Alumina 22.04 



Ferric oxide 16 



Lime 50 



Magnesia .40 



Alkalies V.* 60 



Ignition 5.80 



101.70 



Sand 34.52 



Total fluxes 1.66 



No. 4. This clay as has already been stated is a 

 low grade bauxite, it is white in color with a slight 

 yellowish tinge and portions of it show a pisolitic 

 structure. It slakes quickly. 31.35 per cent, of wat- 

 er were required to work it up and even then the mud 

 was extremely granular and very lean, and the air 

 dried briquetts had a tensile strength of only 5 

 pounds. The air shrinkage was 5 per cent. At 2250 

 I?, the total shrinkage was 14 per cent., the bricklets 



