GLOSSARY. 167 



TAIL RACE An aqueduct for conveying away dirty water and 



tailings. 



TAN (China) Weight = 133$ Ibs. 

 TARNISHED Having the lustre altered by exposure. 

 TEARY GROUND Ground easily broken up or worked. 

 TERTIARY ROCKS Those of the most recent formations, and above 



the Secondary and Primary. 

 THERMAL, HOT (e.g. thermal springs). 



TINSTONE Ore containing small grains of oxide of tin ; tin ore. 

 TIN STUFF Ore obtained from a tin lode. 



TON OF FIREWOOD (Australia) Average of 50 cubic feet of wood. 

 TOURMALINE A gem, variously coloured, found sometimes in large 



transparent crystals in granite, metamorphic rocks, limestone, 



soapstone, &c. 

 TRACHYTE A volcanic rock containing felspar, sometimes hornblende 



and mica. Has a rough surface when broken. 

 TRANSLUCENT Allowing light to pass through, yet not transparent. 

 TRAP A volcanic rock. Generally grey or greenish. Diorite, 



dolerite, greenstone are varieties. 

 TRAPPEAN ROCKS Certain rocks (such as basalt, &c.), which form in 



terraces. 



TREND The course of a vein. 

 TRIBUTE When miners work on tribute their recompense is a certain 



percentage of the profits derived from the produce of the mine. 

 TUCKER GROUND (Australia) Poor ground, just rich enough to allow 



a miner to buy food and the bare necessaries of life. 

 TUFA (Calcareous) A kind of limestone rock deposited by water con- 

 taining carbonate of lime. Usually porous. 

 TUFA (Volcanic) A rock made up of fragments of ash or other 



volcanic matter, more or less cemented together. 

 TYE The point where two veins cross. Also, an adit. 



u. 



UNCONFORMABLE (See Index). 



UNDERLIE Dip. 



UNSTRATIFIED Not arranged in strata. 



V. 



VANNING Washing " tin stuff" by means of a shovel. 

 VARA (Spain) Length =r 33 inches ; the Spanish yard. 

 VEIN STUFF Ore associated with gangue. 

 VITREOUS Glassy. 



VOLATILE Capable of easily passing off as vapour. 

 VUGH A cavity in a rock or lode. 



