﻿Geological Society of London. 179 



honour as of the greater significance, since of all our scientific societies the Geological 

 Society of Lomlon must be deemed that which in all respects is the must competent 

 to form a judgment of those labours it has specifically named as justifying its decisioti 

 in my own case. It is a somewhat trying ordeal, even to one of scientific achievement 

 far beyond anything to which I can pretend, to hear his own work (as is usual on 

 occasions such as the present) trumpeted forth from the Presidential chair before such 

 an assemblage of eminent men, best capable of weighing their merits or demerits, as 

 that I now see around me. I fear, Sir, that a good deal of the sunny colouring 

 spread by you over whatever I may have been able to add to our knowledge of certain 

 branches of Physical Geology, must become toned down to more sober tints, when, in 

 future years, what I have been able to do shall be examined by the steady light of the 

 study of the s-tudents and philosophers of a future age. It is given to no man so to 

 interpret nature that his enunciation of her secrets shall remain for ever unmodified 

 by the Inbours of his successors. Nor am I vain enough to imagine that the two 

 subjects for which you have principally awarded me this medal can be exempt from 

 that which is the common lot of all advances in science. What I have enunciated 

 with respect to the laws of earthquake movements will fundamentally, I believe, 

 admit of little of very radical change by the future advances of Physical Geology ; for 

 the laws I have assigned to seismic phenomena come so close to, and are such direct 

 consequences of well-understood physical laws, as to be, like those laws, immutable ; but 

 in details future discovery cannot fail to alter something, and vastly to add to that I 

 have been privileged to announce. For example, it was my own good fortune to 

 ascertain, observationally and experimentally, the depth below the earth's surface 

 whence the impulse came of the first earthquake ever submitted to measurement. 

 That in the case of the great Neapolitan shock of 1857 proved to be only about eight 

 or nine geographical miles ; but it is highly probable that the depth of the centre of 

 impulse of many great earthquakes may greatly exceed this, and may be found to bear 

 some relation to the height of the greatest mountain-ranges adjacent. Thus my old 

 friend. Dr. Oldham, after his examination of the region of the great Cachar earthquake 

 a few years since in North-eastern India, found that its centre of impulse may have 

 been thirty miles in depth from the surface. The views which I have enunciated as 

 to the nature and origin of volcanic heat and energy, though I believe they will be 

 ultimately found to be in the main a true interpretation of nature, must, I expect, 

 be subject to large modification and addition in the future advances of knowledge. 

 Our physical data in their numerical relations are still too defective to enable us to do 

 much more at present than to sketch the general scheme of the laws of volcanic 

 action, which must, by the way in which they fit into or explain many natural 

 phenomena in widely diverse regions of nature, seem to afford credentials of their own 

 reality in nature. 



In making these remarks, I have, perhaps, already exceeded the limit that properly 

 belongs to an occasion like the present ; and, in conclusion, let me once more repeat 

 my thanks for the kindness, sympathy, and appreciation with which you have to-day 

 marked your approval of what little I may have been able to do for the advancement 

 of our common object. 



The President then presented the balance of the proceeds of the Wollaston Donation 

 Fund to Mr. Robert Etheridge, jun., F.G.S., and addressed him as follows : — 



Mr. Eobert Etheridge, — I have great pleasure in handing to you the balance of the 

 proceeds of the Wollaston Donation Fund, which the Society has awarded to you as 

 a testimony of their appreciation of your industry and accuracy as a Palajontologist. 

 You have laboured with great success amongst the fossiliferous rocks of Australia, and 

 now you are advancing palseontological science by describing the rarer fossils of the 

 invertebrate series from the Scottish Carboniferous formation. In offering you this 

 distinction, I venture to hope that its reception will stimulate you to further inquiries 

 into the Palaeozoic faunas. 



Mr. Etheridge replied : — Mr. President, — The recognition by the Council of the 

 Geological Society of my labours, by the award of the Wollaston Fund, is both 

 gratifying and complimentary to me. I have been and am still making gieat 

 endeavours to elucidate some branches of our common science. For your awarid 

 I beg to tender my sincere thanks. It will stimulate me to further exertions. 

 The systematic study of the British Carboniferous Mollusca, to which I have more 

 particularly confined my attention, has been for many years comparatively neglected, 

 notwithstanding the vast amount of material gathered together through the energy 

 and zeal of local scientific men, many of them distinguished members of our Society. 



