ANNIVERSARY ADDRESS OF THE PRESIDENT. xlvii 



doubt for a moment that one of the greatest advances ever made in 

 the descriptive section of his science was the estabhshment of the 

 Silurian system. It matters not whether we hold, with its author, 

 that the earliest manifestations of life and the commencement and 

 inauguration of animated nature are included within it ; or, with Sir 

 Charles Lyell, more cautiously interpret the relics of prim.aeval 

 beings, and regard the Silurian fauna as the earliest yet demonstrated, 

 though not necessarily the first. Whichever view we take, the im- 

 portance of the discovery and definition of the Silurian system cannot 

 be called in question. It was a grand reward of sagacity, perseve- 

 rance, and well-directed skill — no lucky chance, but a discovery 

 deliberately sought, which threw a flood of daylight around a realm 

 of geological darkness, and made the obscurest of rock assemblages 

 one of the clearest and most instructive. A single man did this great 

 and worthy task. The definition of the Silurian system, and the 

 several members or sections of which it is composed, the invention of 

 a nomenclature for the subdivisions, which, though essentially local, 

 has become of universal application, the determination of a scheme 

 of organic types upon which comparisons and identifications could 

 be conveniently based — all these good works were done by one inves- 

 tigator, the illustrious author of the volume now before us*." 



I have also to notice a paper by Professor Sedgwick, "On the May 

 Hill Sandstone and the Palaeozoic System of the British Isles." I 

 am not about to attempt any discussion of the vexata qucestio be- 

 tween Professor Sedgwick and Sir R. Murchison respecting the 

 nomenclature of the earliest palaeozoic formations, or to explain what 

 amount of error or of truth there may be in the respective views of 

 these two distinguished men ; I will only observe that, in support of 

 his views. Professor Sedgwick endeavours to show in this paper that 

 there is no continuous unbroken section ascending from the Cambrian 

 to the overlying Silurian groups, but that there is a physical break 

 between them exactly on the horizon of the May Hill Sandstone, 

 and that, in co-ordination with that break, there is a great change in 

 the fossil species. The value of this evidence depends on its being 

 shown to be general, and not a merely local phsenomenon. 



The Ordnance Geological Survey has been satisfactorily progressing 

 during the past year, and it is gratifying to know that Sir H. 

 De la Beche and his able staff have at length been enabled to direct 

 their attention to the survey of some parts of Scotland. This has 

 been rendered possible by the Trigonometrical Survey having now 

 completed a sufficient portion of the map to admit of the geological 

 features being laid down. In England the survey is being extended 

 to the central counties, and here also we may expect some results of 

 more than ordinary interest, inasmuch as its extension involves the 

 question of the distribution of the Coal under the New Bed Sandstone. 

 One of the most interesting results of the labours of the Survey 

 during the past year has been Mr. Salter's investigation of the lower 

 Carboniferous rocks in Pembrokeshire and North Devon, confirming 

 views formerly held by Sir H. De la Beche, viz. that the upper part 

 * Quarterly Review, No. cxc. Sept. 1854, p. 385. 



