ON COLOURING GEOGNOSTICAL MAPS. l6l 



' Black-coal. 



Porphyry. 



Sienite. 



Brown and^ 

 Earth coah $ 



BROWN COLOURS. 



Pale blackish-brown, approaching 

 to yellowish-brown. 



Pale reddish-brown, slightly in- 

 clining to yellowish-brown. 



Pale reddish-brown, falling into 

 bluish. 



Liver-brown. 



