Am. Jour. Sci., Vol. XXXVII, 1889. 



Plate IX. 



SKafi„a>„Xevel e/'Room'S 

 SbaSetsiup. 



Sfiaftl Lexel 6, Room-ft 



HORIZONTAL SECTIONS OF LUDINGTON MINE. 



EXCEPT FIG. 10. WHICH IS A VERTICAL SECTION. 



