Mining Terms. 167 
Downcast. A ventilating shaft with descending 
eurrent of air. . : 
Dump. A deposit, or place of deposit, of waste 
rock or tailings. 
Evan Coursr. A plutonic dyke. Lyell. Argall. 
Corn. | 
Eye. The top of a shaft. 
Facr. Synonymous with breast. 
FatHuom. A space 6 feet forward and 6 feet ver- 
tical with the width of the vein. Corn. 
Fautt. A dislocation of the strata. Bainbridge. 
Yale. The dislocation of a vein from its original posi- 
tion; a heave; a throw. Von Cotta. 
Freper. A small vein starting from some distant 
point and running into a main lode. It is practically 
synonymous with spur. See Bainbridge. 
Fevpspar. A vitreous crystalline constituent of 
granite, gneiss, porphyry and many other rocks. 
Fissure Vein. A fissure or crack in the earth 
across its strata, filled with mineralized mater. 
Froat. Loose quartz detached from the vein and 
‘ found below it. 
Froat Orr. Masses or particles of ore detached 
from the vein and found below it. 
Frooxan. A soft, decomposed cross-course. Cor- 
nish. 
Fioor. The rock underlying a horizontal vein or 
deposit. 
Frumr: A ditch carried in frame work on or above 
the surface. 
Foot Watt. The under wall of the vein. 
ForFeiture. The loss of possessory title as the 
result of abandonment or the failure to comply with the 
conditions under which the title was held. 
Gap. A small pointed wedge. 
Garena. A sulphide of lead. When not amorph- 
ous, is crystallized on the cubic system; when pure 
contains 86.6 per cent lead, 13.4 per cent sulphur. Car- 
_ Ties silver in greatly varying quantities. 
