Mar. 28, 1872] 



NATURE 



431 



Report (referred to in last week's Nature) on application to the 

 Hon. Secreiaries, King Edward's School, Birmingham, or to the 

 London Local Secretaries, Mr. C. W. Merrifield, F.R.S., South 

 Kensington, and Mr. K. Tucker, University College School. 



Mr. L Lowthian Bell read a paper at the Institution of 

 Civil Engineers on Tuesday evening, March 18, " On the condi- 

 tions which favour and (hose which limit the Economy of Fuel in 

 the Blast Furnace for Smelting Iron." A discussion on the 

 paper was taken at the following meeting on Tuesday evening 

 last. 



Mr. Alfred S.mef, F.R.S., has in the press a volume entitled 

 3Tj Garden, in which he gives a complete description of his experi- 

 mental garden at Beddirgton, in Surrey, and details (he results 

 of his experience in the culture of flowers and fruit: of there 

 nearly 700 species and genera are described. The volume also 

 treats generally of the natural history, geology, and antiquities 

 of the neighbourhood. It is illustrated with about i.cco vcod 

 engravings,^ executed expressly for the work. The volume 

 will be published by Messrs. Bell and Daldy. 



ANNUAL ADDRESS TO THE GEOLOGICAL 



SOCIETY OF LONDON, FEB. 16, 1872 



By J. Prestwich, F.R.S., President 



TN looking at the labours of the Society dunng the past 

 year, it is satisfactory to notice the same activity, the same 

 wide range of subjects as ever, and the same independence 

 of research for truth's sake which there ever should be. But, 

 though gond work has been done in special branches and the 

 technical details of Geology, not so much progress has been 

 made in its higher problems. I would, however, direct your 

 attention to the steps made in grouping our volcanic rocks, and 

 in the determination of the fauna of our Cambrian strata, which 

 proves to be so much larger and richer than was anticipated a 

 few years back. Both these subjects are in able hands, and can- 

 not fail to yield important result.=, the latter especially in aiding 

 to settle that interesting question — the true line of division 

 between the Silurian and the Cambrian formations. On the 

 subject of denudation and river-action, we have also had several 

 excellent papers, and look forward with interest to the further 

 development of the many original views which they have put 

 before us. 



The great question of the history of our globe during the 

 Quaternary period seems also to be advancing towards more 

 completeness. Many able observers, both in and ou^ of our own 

 Society, are engaged upon the subject, and various scientific 

 periodicals and publications of our local societies are rich in 

 contributions bearing upon this interesting subject. There is no 

 more wonderful chapter in the earth's histoi7 than that which 

 embraces the phenomena connected with the prevalence of great 

 and exceptional cold immediately preceding our time, — the first 

 dim appearance of man — his association with a race of great extinct 

 Mammalia belonging to a cold climate — the persistent zoological 

 characters of the one, so far as we have yet gone, in opposition 

 to the variable types presented in geological time by the others — 

 the search for connecting links, and the measure of man's .inti- 

 quity, — all of which constitute theoretical problems of the highest 

 interest, and are now occupying the attention of geologists of all 

 countries. Allied also to this subject are the gi'eat questions 

 relating to the form of our present continents — the elevation of 

 the land — the origin of valleys and plains — and of all that which 

 prepared this globe for the advent of man. 



But while treating of these abstract and philosophical ques- 

 tion.s, geology deals also with the requirements of civilised man, 

 showing him the best mode of providing for many of his wants, 

 and guiding him in the search of much that is necessary for his 

 welfare. The questions of water-supply, of building materials, 

 of metalliferous veins, of iron and coal-.supply, and of surface- 

 soils, all come under this head, and constitute a scarcely less im- 

 portant, although a more special branch of our science than the 

 palasontological questions com ected with the life of past periods, 

 or than the great theoretical problems relating to physical and 

 cosmical phenomena. Looking at this triple division of geology, 

 and seeing that the first, or applied geology, is, as it were, only 



incidental to our general studies, and therefore not often the topic 

 of our discussions, notwithstanding its practical importance, I 

 propose on this occasion to say a few words in connection with 

 the two momentous subjects which, during the last few years, 

 have been made the objects of investigation by two Royal Com- 

 missions,* on both of which the geological questions have re- 

 ceived much and careful consideration. I shall here restrict my- 

 self to the more special geological bearings of the subject, 

 extending them, however, in some directions beyond the scope 

 of the original inquiries, and refer you to the Reports and 

 Minutes of Evidence themselves for the many valuable economical 

 questions and practical details which are there discussed. 



Our Spiings and Water-supply. 



The site of a spring or the presence of a stream determined 

 probably the first settlements of savage man ; and his civilised 

 descendants have continued, until the last few years, equally de- 

 pendent upon like conditions — conditions connected first with the 

 rainfall, and, secondly, with the distribution of the permeable 

 and impel meable strata forming the surface of the country. 

 Under ordinary circumstances, few large towns have arisen except 

 where there has been an easily accessible localised water-supply, 

 and where the catchment-basin on which depends the volume of 

 the rivers has been large, and permeable strata prevail. Take, 

 for example, London. Few sites could be more favourable in 

 every respect. Beneath it are strata rich in springs, while at a 

 distance there is that large development of those massive per- 

 meable strata so necessary to maintain a sufficient and permanent 

 flow in our rivers. As the conditions exhibited in the London 

 basin afford all the illustrations we need for our subject, I will 

 confine myself in this address to that area alone. 



London north of the Thames stands on a bed of gravel, varying 

 in thickness from ten to twenty feet in round numbers, and over- 

 lyingstralaoftenaciousclayfrom lootozoofeet. The former being 

 easily permeable, the rain falling on its surface filters through it, 

 until stopped by the impermeable London clay, where it accumu- 

 late< and forms a never-failing source of supply to the innumer- 

 able shallow wells that have been sunk all over London from time 

 immemorial, and which for centuries constituted its sole water- 

 supply. Not only does it form an easily accessible underground 

 reservoir, although of limited dimensions ; but where the small 

 intersecting valleys cut down through the bed of gravel into 

 the London clay, a portion of the water in this reservoir escapes 

 at the junction of the two strata, and gives rise to several springs 

 formerly in much repute, such as those of Bagnigge Well, Holy- 

 well, Clerken-well, St. Chad's Well, and others. 



The early growth of London followed unemngly the direction 

 of this bed of gravel, eastward towards Whitechapel, Bow, and 

 Stepney ; north-eastward towards Hackney, Clapton, and 

 Newington ; and westward towards Chelsea and Kensington ; 

 while northward it came for many years to a sudden tenni- 

 nation at Clerkenwell, Bloomsbury, Mar)lebone, Paddington, 

 and Bayswater ; for north of a line drawn from Bayswater by 

 the Great Western station, Clarence Gate, Park Square, and 

 along the north side of the New Road to Euston Square, Burton 

 Crescent, and Mecklenburg Square, this bed of gravel terminates 

 abruptly, and the London clay comes to the surface, and occupies 

 all the ground to the north. A map of London, so recent as 

 1S17, shows how well-defined was the extension of houses arising 

 from this cause. Here and there only beyond the main body of 

 the gravel there were a few outliers, such as those at Islir"ton 

 and Highbury ; and there habitations followed. In the same 

 way, south of the Thames, villages and buildings were gradually 

 extended over the valley-gravels to Peckham, Camberwell, Brix- 

 ton, and Clapham ; while, beyond, houses and villages rose on 

 the gravel-capped hills of Streatham, Denmark Hill, and Nor- 

 wood. It was not until the facilities were afforded for an irde- 

 pendent water-supply by the rapid extension of the works of the 

 great water companies, that it became practical)le to establish a 

 town population in the clay districts of Holloway, Camden 

 Town, Regent's Park, St. John's Wood, Westboume, and 

 Notting Hill. 



On the outskirts of London a succession of villages grew up 

 for miles on the great beds of gravel ranging on the east to 

 Barking, Ilford,and Romford — on the north, following the valley 

 of the Lea to Edmonton and Hoddesdon ; and on the West, up 

 the Thames-valley to Ealing, Hounslow, Slough, Hammersmith, 



* Royal C 

 the Commis 



— .1 Water Supply, appointed April 1E67. Report of 

 nd Minutes of Evidence and Appendix, June jgeg. 



lilt ...UJiiiiiia^iuiicia etiiu iiJluuica Oi jz-vjuculc ailU rtppenODC, JUne J tfcO. 



P oyal Commission on Coal Supply, appointed June 1866. 



Reports of the Comnussionert, Minutee of Evidence, Appendix, July 1871 



