Dale — Brag-Folding in Alabama Marble. 319 



Akt. XXIY. — On Concentric Drag-Folding in Alabama 

 Marble; by T. Nelson Dale. 



While engaged in collecting material for a U. S. Geo- 

 logical Survey Bulletin on the marbles of the Southern 

 States, the writer, on Oct. 23d, 1916, noticed in the storage 

 yard of the Moretti-Harrah quarry near Sylacauga, in 

 Talladega County, Alabama, several marble blocks con- 





No. 1. — Block of white marble (6 ft. hj 4 ft. 6 inches) from the Moretti- 

 Harrah quarry near Sylacauga, Ala., showing lenses bounded by films of 

 muscovite schist. The drilled face is parallel to the strike of bedding. 



taining lenses up to 2 ft. in diameter and 6-8 inches in 

 thickness. These lenses were separated from the marble 

 mass by a film of muscovite schist. Two of these blocks 

 with lenses are shown in the reproduced photographs, 

 figs. 1 and 2. Some blocks afforded two vertical sections 

 of the same lens at right angles to one another, thus leav- 

 ing no question as to their being really lenses. 



