TEE GEOLOGY OF li'OIiLI HILL. 



595 



there were any fishes; the probability is that there may have been some ia th^ 

 deeper waters. Very minute shell fish of one or more species was fairly plentiful' 



Then came the great catastrophe of the lower trap. Bursting under the 

 sedimentary beds it broke up some of them and lifted up the remainin.. into 

 a ndge fracturmg and faulting them in the process. The trap had not'force 

 enough, however, to pierce thi-ough this 30 ft. thickness of aqueous deposits as 

 no dykes have been met with. The heat of this volcanic matter does not seem 

 to have been very intense, though through its mechanical effects some of the 

 faulted strata must have become partially fused. The life of the lake as such 

 came to an end ; it was left high and dry. Carter on the contrary thinks that 

 It was the effusion of the upper trap that put an end to this lake. He says : 

 "It is most probable that the lake was above the level of the sea at the time 

 this (i.e., the effusion of the upper trap) occurred although the general level 

 of its strata is now below it. One another fact connected with the fresh water 

 formation is here worth mentioning, viz., that within three inches of the igne- 

 ous rock which overlies it there is a stratum three inches in thickness almost 

 entirely composed of the casts of ' Cyprid(e\ not of their valves singly which 

 they are want to shed annually but of their entire casts, showing that some 

 sudden alteration of the water in which they were living took place, by which 

 they all as suddenly perished and fell to the bottom. After this occurrence 

 no organic remains are seen, and nothing but the three inches mentioned of a 

 kind of transitional material between the fresh water formation and the basalt."' 

 If the " Cypridce " met their death from the waters heated by the effusion of 

 the upper trap there would be no time for the deposition of the three inch layer 

 of transitional material. Moreover the molten trap which must have been 

 in a highly fluid state would have fused the material with which it came in 

 contact and together with it the casts of the " C3^prid8e." The probability is 

 that they died of other causes and further aqueous deposits took place until 

 the lake was raised into a ridge by th3 irruption of the lower trap. The 

 surface of the sedimentary beds had had no time to become extensively weather 

 ed before the flow of the upper trap occurred and covered the whole land with 

 a dark mantle. Life came to an end and thousands of years must have elapsed 

 before vegetable and animal life reappeared on the cooled plains. 



Geological data are invariably collected from excavations made in the earth 

 for industrial or non-scientific purposes ; or from natural exposures of the 

 rocks. No deUberate excavations are generally made for geological researches. 

 It is quite likely that further quarrymg of the Worli Hill may bring to light 

 other interesting facts, minerals and fossils, and what is stated in this paper 

 may have to be greatly modified or added to in view of the subsequent disco- 

 veries. This paper is intended merely as a record of the things found at and 

 the provisional conclusions drawn from the excavations now going on bi>t\v\-o!i 

 the Love Grove sewage outfall and the Western India Brick Factory. 



