188 DETAILED REPORT ON ALABAMA CLAYS. 



F., the to'al shrinkage w..s 8 per cent, and the color of 

 the bricklet was a rich red. At 2100 F., the color of 

 the bricklet was the same, and the -shrinkage was 9 per 

 cent., incipient fusion having occurred at this point. 

 Vitrification occurs at 2200 F., and the color is deep red, 

 while viscosity took place at about 2300 F. In drying 

 the clay showed little evidence of containing any appre- 

 ciable quantity of soluble salts that would tend to form 

 any efflorescence, nor did any show themselves afetr 

 burning. 



The comparatively small shrinkage and the rich red 

 color to which the clay burns would make it ad- 

 mirably adapted to the manufacture of pressed brick, but 

 unless it was mixed with a more plastic clay it would 

 hardly work for the production of terra cotta. 



The semi-weathered character of the material would 

 also facilitate the preparation of it. 



(No. A.) 

 PAVING BRICK CLAY, 



TEN MILE CUT, TUSCALOOSA CO. 



.The sample of this clay was collected by the writer 

 from what is known as the Ten Mile Cut on the M. & 0. 

 R. R., west of Tuscaloosa. It is a somewhat gritty clay, 

 which contains thin seams of sand. The general color of 

 the clay is bluish-gray, but here and there it shows stains 

 of limonite especially on the sandy fractures. Wh^n 

 thrown into water it slakes and gives in working a some- 

 \*hat gritty, but quite plastic mass, which requires 26.00 

 per cent, of water to work it up. 



The air shrinkage of the cky amounted to 8| per cent, 

 while at 2200 F., it was only 10 per cent., and at 2300 

 F., 12 per cent., at which point incipient fusion occurred. 



