136 GEOIOOY. 



sulphur, limestone, gold, rock-tar, mineral waters, and traces of silver, 

 lead, zinc, manganese, and copper. F. D. 



Mallet, P. R. Geology of Darjiling and "Western Duiirs. Mem. 

 Geol. Surv. Ind. vol. xi. pt. 1, pp. 96, 2 maps. 



Begins with a geographical description of the Darjiling district and a 

 general sketch of the rocks. A section from south to north gives the 

 prinid facie appearance of a great synclinal ; but this, as regards the 

 outer (Tertiary) rocks, is deceptive. North of the Tertiaries is a nar- 

 row band of the Damiidas, which include beds of anthracite. Overlying 

 these, without apparent unconformity, are some thousand feet of slates. 

 Ascending the hills, the slates pass through mica-schist to gneiss ; the 

 relation of these groups of rocks to each other is obscure. Then follows 

 a detailed description of the different series of rocks. The Damudas 

 have been much crushed, and in places metamorphosed ; the crushing 

 has also caused the thickness of the coal-beds to vary much within a 

 few yards. A detailed section of more than 1800 feet of these beds is 

 given. The Baxa series is then described : it consists of some thousand 

 feet of slates, schist, quartzite, and dolomite ; these are largely developed 

 in the W. Duars, but only occur in the extreme E. end of the Darjiling 

 territory. Since they occupy diiferent areas, the relation of the Da- 

 muda and Baxa series is not clear. I^ext comes an account of the 

 Daling slates, which rest conformably on the Damudas ; these slates, 

 again, dij) under gneiss, which is called " Darjiling gneiss." Next are 

 the Tertiaries which fringe the older rocks ; they are many thousand 

 feet in thickness ; along one part of the edge of the hills, however, they 

 are absent, probably from denudation. The latter part of the Memoir 

 is devoted to Economic Geology. Several outcrops of coal have been 

 measured (of how many seams one cannot tell), which show a thickness 

 varying from 2 to 11 feet. The dip is generally high. Assays show 

 70 per cent, of free carbon from one locality and 66 per cent, from 

 another ; the coal is very flaky ; the prospects of mining it are discussed. 

 Iron-ore occurs in some places ; copper also is found, and the native 

 mode of mining and smelting it is described. F. D. 



. Geological Notes on N. Hazaribagh. Bee. Geol. Surv. Ind. 



vol. vii. pt. 1, pp. 32-44, plate. 



Describes the area in two sheets of the Survey Map. The rocks 

 (chiefly metamorphic) are carefully described. Gneiss occupies a por- 

 tion of the area; with this occurs a band of dolomitic limestone. 

 Mica-schist and quartzite overlie the gneiss, but no distinct unconfor- 

 mity has been observed in this area ; hornblende rock and schist also 

 occur. Pegmatite (defined as a coarse mixture of quartz, felspar, and 

 silvery mica, often containing tourmaHne) occurs through both the 

 gneiss and the schists, penetrating them in dykes and veins, and occa- 

 sionalty occurring in isolated lenses ; contact- sections of the granite 

 and schists are shown in the plate. Trap-dykes were also observed. 

 In one locality sandstone with pebbles, 20 feet thick, probably belonging 

 to the Talchir group, was seen. 



