HARD Wl CKE ' S S CIE NCE-G OS SI P. 



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showed, from iacts recently made known, that while 

 geological evidence is against its igneous origin, 

 all the gold of all the rocks may have been derived 

 from aqueous deposition ; that, in fact, all this 

 gold may have been deposited by marine action in 

 the same way as the materials of the aqueous rocks 

 themselves have been. And, moreover, our un- 

 altered sedimentary rocks, even of tertiary age, may 

 contain an equal amount of gold in proportion to 

 their bulk with that of those altered or metamorphosed. 

 Cambrian and Silurian rocks which have hitherto 

 been regarded as the earth's great treasures of the" 

 precious metal. The knowledge now possessed of 

 secondary and tertiary auriferous veins in California 

 ' controverts the Plutonic as well as the palreozoic 

 hypothesis ; and the discovery of gold in sea-water, 

 and of its precipitation by organic matter, alters the 

 position of the question from that it occupied in the 

 days' of Murchison and Forbes. If gold was originally 

 derived from Plutonic sources it ought to be found 

 among volcanic products which come from the same 

 deep-seated sources, and only differ from Plutonic 

 rocks in being solidified under different conditions. 

 But gold, although a most widely distributed metal, 

 is almost, if not quite, unknown as a product of 

 volcanic regions. This is strongly against its igneous 

 origin, and consequently points to the gold of the 

 palaeozoic auriferous veins being derived by removal 

 from sedimentary rocks in which it had been originally 

 deposited. This removal could be effected by 

 chemical combination, solution, infiltration, and 

 segregation. Since silica may combine with gold 

 under heated conditions, and the silicate of gold so 

 formed be soluble in hot water, as is also silica, gold 

 in the form of silicate could be carried by water, 

 heated by deep-seated conditions or by the neigh- 

 bouring uprise of fused matter, from its original 

 position, and be deposited in veins with silica itself, 

 when subsequent segregation would separate the silica 

 of the silicate of gold and leave it as free gold im- 

 bedded in quartz as it is now found. The discovery 

 by Sonstadt of nearly a grain of gold to the ton of 

 sea-water shows that the sea has always held in 

 solution an ample store to give to its sediments the 

 amount of gold they are now found to contain, and 

 Daintree's discovery of the power of organic matter 

 to precipitate gold from a solution of the terchloride 

 explains the deposition of gold from sea-water, since 

 on the sea-bottoms there has always been a large 

 amount of organic matter. Though the gold so 

 deposited would be in infinitesimal proportion to the 

 mass of the marine mineral sediments, it would be 

 aggregated by nuclei of metallic sulphides by which 

 it would be retained until thermal conditions favoured 

 its conversion to a soluble silicate. The sulphide of 

 iron, or pyrites, is known to nearly always contain 

 gold, and hence it is to be concluded that the gold 

 of the sedimentary rocks which have not been sub- 

 jected to the favouring conditions for its separation 



and preservation in quartz veins is now in the metallic 

 sulphides these rocks contain. In such rocks as the 

 chalk and the London clay, the amount of pyrites is 

 very great ; and the author concluded by giving a 

 rough estimate of what may be the amount of the 

 gold now in the surface-rocks of the south-east of 

 England, from which it appears that these deposits 

 may contain gold to the value of ,£100,000,000 

 sterling. 



Fossil Horned Lizards. — At the recent meet- 

 ing of the British Association, Professor Marsh, 

 of the United States, gave an interesting account 

 of his discoveries with regard to the gigantic 

 Ccratopsidcs or horned dinosaurs. During the 

 last two years Professor Marsh has been working 

 at certain beds called Laramie, near the Rocky 

 Mountains. The true character of these beds was 

 formerly doubtful, but it has now been found by 

 examination of the flora that the lower part is true 

 cretaceous, and that the upper part is tertiary. In 

 the true cretaceous these Saurian remains have been 

 discovered. They are of great size, and the blocks 

 in which they are embedded sometimes weigh as 

 much as two tons. Securing them has been a work 

 of great difficulty, and called for the exercise of 

 much engineering skill. The remains, diagrams of 

 which were exhibited, differ from those most familiar 

 to European workers. The skull is of great size, 

 and is characterised by two large horn cores near the 

 eyes, and by one smaller horn core on the nose like 

 that of the rhinoceros, extending a considerable way 

 backwards, where it appears to be armed by rudi- 

 mentary cores. The teeth also are peculiar in having 

 fangs implanted crosswise in the adult. The length 

 of the skull is quite 8 ft. ; the brain is relatively very 

 small. To bear this enormous weight there are 

 peculiar modifications of: the neck, vertebra;, and of 

 the four limbs. Professor Marsh was disposed to 

 refer this Ceratopside to a distinct order of the dino- 

 saurs. 



Earth Movements in Pre-Cambrian and 

 Paleozoic Times. — Dr. Henry Hicks, F.R.S., 

 F.C.S., read, a paper, in the Geological Section, on 

 " The Effects produced by Earth-Movements on 

 Pre-Cambrian and Lower Palaeozoic Rocks in some 

 Sections in Wales and Shropshire." He gave 

 examples to show the powerful influences exerted by 

 earth-movements in producing changes in the rocks, 

 and in obliterating the evidences of succession in the 

 disturbed areas in Wales and Shropshire. He 

 pointed out that the difficulties experienced by 

 geologists who examine these areas for the first time 

 are mainly due to their being unable, or unwilling, 

 to recognise the extraordinary effects produced by 

 these earth-movements, and especially the complica- 

 tions due to faults and thrusts. Frequently portions 

 of the pre-Cambrian rocks have been forced in among 

 the Lower Palceozoic rocks so as to appear either to 



