ON COLOURING GEO GNOSTIC AL MAPS. 



Grey-wacke. 



*59 



Greenish-grey, inclining to yellow- 

 ish-grey. 



Flcetz-lime stone. Pale bluish-grey, without any trace 



of green. 



Calc-tuff. Smoke-grey. 



Loam and Clay. Yellowish-grey, passing to ochre- 

 yellow.' 



Flinty-slate. Ash-grey. 



Basalt, 

 Alum- slate. 



Porphyry-slate. 

 Amygdaloid. 



BLACK COLOURS. 



Greenish-black. 



Pale bluish- black, passing into 



greyish-black. 

 Pale greenish-black. 

 Pale greenish-black, passing into 



brownish-black. 



BLUE COLOURS. 



Gneiss. Lilac-blue. 

 Granular pri-^ 



mitive lime- V Pale Berlin blue. 



stone. J 

 Compact pri-^ 



mitive lime- y Smalt blue ? slightly inclining to red. 



stone. J 



Transition-"} Indigo blue, slightly inclining to 



limestone, § grey. 

 Gypsum. p a ] e sky-blue. 



