PAET ].] 
Clark : On Volcanic Foci of Friiption in the lionhan. 
73 
country between tbe ghauts and the sea, it occurred to me that what I there saw was 
not unlike what would be seen if the island of Sicily were to be submerged, and Etna 
be acted upon by water currents. The central part, being shattered, would easily 
be removed down to the nuclei of the several craters, and the flanks of the 
mountain being much less shaken would remain and present more or less of 
a scarp at their innermost and highest edge, and their surface, like that of the 
Deccan near the ghauts, would be hollow^ed into ordinary valleys of excavation. 
If for a single central point one or more lines of action were substitirtcd, the 
efiiect would be pretty much what is now' seen in the Konkan. Possibly the same 
effect would be produced by atmospheric action, only in such a case an enormous 
period of time w'ould be necessary. 
Then, as to the contrast betwmen the beds forming the ghauts and those in 
Bombay and Salsette, the former at a certain distance from the line of action 
fall with a uniform and gentle slope, whereas the western beds fall at an opposite 
and much greater dip, and are more or less broken. This I supposed to be due 
to the previous configuration of the ground. I thought the base of Konkan and 
the Deccan to be a mass of metamorphic I’ock, over which the trap flowed at an 
easy slope, while to the west the same trap flowed into the deep sea. I under¬ 
stand, however, that late researches are opposed to this latter notion, and that 
there is reason to think that the greater dip of the western bed is due to a sub¬ 
sequent subsidence. This, of course, does not materially affect the question of the 
common sources of these rocks. 
I remark also that the present, and I dare say the correct, opinion is that these 
traps are subaerial and volcanic. I supposed them to be submarine and j)lutonic, 
because they seemed to me to have been erupted under immense pressure. This 
again does not materially affect the leading inferences derived from my obser¬ 
vations. 
In concluding this long and, I fear, tedious letter, I may be allowed to re¬ 
mark that it is many years since I have paid attention to this or any other geo¬ 
logical subject, and that neither formerly nor now have I any pretensions to bo 
called a geologist. I brought home with me a vast collection of samples from 
every dyke I met with, each labelled with the direction, breadth and leading features 
of the dyke. I sent these in 1848 or 1849 to the Geological Society, where they 
were seen by Mr. Horner and the then Secretary Mr. Lonsdale. These gentlemen, 
however, did not think them worth the space they occupied, and as they declined 
them, I caused them to be thrown aw'ay, nor did I again trouble myself on the 
subject, until some years afterwards I saw to my surprise my name mentioned 
in a paper by Mr. Wynne as one of the pioneers in the geology of Bombay. 
I am not sorry even now to find or make an opportunity of bringing under 
your notice as the head of the Indian Survey a sketch of what I did in the field 
so many years ago. You are necessarily aware of the difficulties attendant upon 
field work in the Konkan, and will therefore extend to my labours that charity 
that I suspect they much require. 
I add a tracing of a map showing a few of the centres of action, and most 
of tbe dykes observed in the Malsege or tow'ards Kalian. 
K 
