1859.] HISLOP GEOLOGY AND FOSSILS OF NAGPUR. 155 



and sedimentary, with which those fossils are connected. They have 

 already been noticed in a memoir, which, in conjunction with my 

 friend the Rev. It. Hunter, I submitted to the Society in 1854*. 



On that occasion I endeavoured to prove that there was no foun- 

 dation " for the supposition that the great outpouring of basalt in 

 India took place in the ocean," — that the water of the lake in whi h 

 it really was effused was in many places " so shallow as to allow the 

 igneous rock to rise above its surface into the atmosphere," and that 

 therefore the flatness of the tops of trap-hills was not owing to su- 

 perincumbent pressure, as is generally believed, but was " the effect 

 of the well-known law by which the surface of liquid bodies is re- 

 duced to the same uniform level." The age of the deposit formed at 

 the bottom of the lake, before it was invaded by the volcanic erup- 

 tion, I considered to be Lower Eocene ; and, while inferring as a 

 matter of course that the overlying trap was subsequent to it, I 

 expressed the opinion that the similar rock which was frequently 

 found underlying was more recent than both. 



In opposition to this last view it is held, that the underlying trap 

 must have been poured out first, and the freshwater deposit formed 

 over it. This, I admit, would be the theory attended with the fewest 

 general difficulties ; but the objection to it in my opinion is, that 

 it does not apply to the case under consideration. If it did, we 

 should expect that, at the junction of the deposit with the sub- 

 jacent amygdaloid, the former would partake of the colour of the 

 latter, whereas there is most frequently a marked difference between 

 them in that respect. In fact, instead of the deposit being com- 

 posed of the detritus of the friable amygdaloid, I believe it will be 

 found, on the contrary, that the friable amygdaloid consists in a great 

 measure of materials altered from the deposit. Capt. Newbold's 

 analysis of amygdaloid underlying red clay warrants this statement, 

 though he docs not seem to have perceived the inference deducible 

 from it regarding the relative age of the vesicular trap f. 



But should this chemical proof not be enough, there is mecha- 

 nical evidence at hand. About two miles to the west of Telan- 

 kber/i, and five in the same direction from Nagpur, we have a natural 



* Quart. Jouni. Geol. Soc. vol. x. p. 47<h vol. xi. p. 345, & p. 655, with Map. 

 t Bee Journal It. Asiat. Soc. vol. ix. p. 85, where Newbold says: " I found the 



basis of the amygdaloid in which /.oolitic crystals WON most abundant to be a 

 red clay." The import of this remark will bo best brought out by B reference to 



theSindaghi section alluded to in another part of this paper. En that section 



between the middle and upper scam of kunkcr there is represented in the WOOd- 

 ent a considerable thickness of "red amygdaloid with zeolites and oalo-SpaT," 



and it is added in the lotlor-pross. •• In this \ieinity beds from three to six Feet 



t luck occur in the amygdaloid ofs finely laminar, bright red bole." Now. look- 

 ing at the figure, in which the calcareous matter is s,, tiiin iii„t j) is r epre s en ted 



only as -cams, wo naturally feel disposed to ask. Where is the deposit, which in 

 the " vicinity " attains a thickness nf " from throe to six feet"? The i-nl\ appro- 

 priate repli to tin- question, in mj judgment, is, that it is to be found in the red 

 and brownish-green amygdaloid, whioh, though still retaining its colour, hai 

 transformed from the clay, while the calcareous portion has been segregated in 

 tlir process. B. II.. June 22, 1859. 



