SALINE GROUP. 75 



the locality and with coaly-looking- highly bituminous shales oecurrino- 

 as a pocket or small lenticular mass."^ 



In several places^ and apparently low down in the salt marl, hard, 

 thin, dark, platy, gray, or greenish layers of what appears to be also 

 a sandy dolomite with shaly partings, have been met with in several 

 places: they may perhaps be the thin beds of chert and silicious sinter 

 of Dr. Fleming^s paper (p. 240). 



In a few spots — fewer even have been placed on record by others— 

 I have met with some irregular patches of a dark 



Trap. , 



purple compact to earthy volcanic-looking rock. 



It occurs associated with gypsum and red marl close to the upper surface 

 of the saline series, just below the purple sandstone (No. 2). • It has the 

 appearance of a diorite, and is associated with paler purple "volcanic tufa 

 or ash. It is crowded with stellate accicular crystals of what may be 

 decomposed actinolite,t and contains strings and nests of talc, small 

 geodes of reddish and clear quartz and chalcedony, minute cavities filled 

 with reddish calcite, strings of quartz and white specks of some decom- 

 posed mineral not sufficiently abundant for determination. I have not 

 observed this trap in dykes, but in nearly horizontal lenticular layers from 

 a few inches up to 6 feet thick or even more ; in some places between 

 gypsum bands, sometimes having a thin layer of the red marl between it 

 and the overlying sandstone, or, as in the Nilawan ravine, lying between 

 rock-salt and gypsum. Here it is partly decomposed, but may have been 

 15 feet thick. The associated violet or lavender earthy portion is used by the 

 natives instead of soap. J It generally overlies the more solid rock with an 

 irregular thickness up to 4 feet. Mr. Theobald seems to have found 

 this rock in a more dyke-like position altering the adjacent rocks an 



* Some of the shale made a fine blazing fire, decrepitating while burning and leaving 

 much ash, also giving off sulphurous fumes. From this rock Dr. Warth obtained a dark 

 mineral oil by distillation. 



t Tremolite : Fleming, p. 242, and Theobald, p. 676. 



J Not unlike the ashy clays with the volcanic -looking infra-nummulitic laterites in 

 Kachh.— Mem. Geol. Sur., Vol. XI. 



( 75 ) ' 



