1840.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



99 



Manchester, the Royal Irish Society, and the Royal Astronomical Society, 

 sets of Transactions, "as complete as could he made np, liave hceii received 

 The Master-flencral of the Ordnance, tlie Lord-Lientcnant of Ireland, and 

 Colonel Colhy, continue their liberal presents of the English and Irisli Sur- 

 veys; and Captain Beaufort ami the Secretary of the Admiralty have con- 

 tinued the present of the series of Admiralty Cliarts. The Institution is also 

 iudchlcd to Mv. Vignolles for the Busts of Locke and Ur. llutton; to Mr. 

 I'ichl, V.P., for a Bust of the late Henry ilaudslay; and to Mr. Rivers, for 

 tliat of Dr. Karaday. 



The council would wish to take especi.al notice of the large collection of 

 works of the late eminent philosophei-. Dr. Yonng, now deposited in your 

 lihrary. For this great acquisition, the Institution is indebted to the kind- 

 ness and lilierality of his brother, Mr. Robert Yo\uig, who conceiving most 

 justly that every thing connected with so great a benefactor to practical 

 science must be highly valued by this Institution, has made it the depository 

 of these books from the library of his distinguished I'clative. The council, in 

 tluis jmblicly recording their sense of the kindjicss and liberality of Mr. 

 Ivobcrt "loung, would earnestly press upon others the importance of following 

 so noble an example, and of presenting such works as are at their disposal, 

 and of which the hl)rary of the Institution is particularly in need. 



It is announced thro\igli the mediunr of the last Annual Report, that the 

 monument of Telford was nearly finished, and that a site had been selected 

 in Westminster Abbey. The council have now the satisfaction of amiouncing 

 that the monument is fixed in the place destined for it, and they are confident 

 that all who enjoyed the accpiaintance, or knew the merits, of the late dis- 

 tinguished president of this Institution, will rejoice that the memory of one 

 so eminent and so highly deserviug has met with so proper and just a tribute 

 of respect; whilst all, no less than those liy whose liberality the monument 

 was erected, will feci that he has a name which will endure so long as there 

 exists a record of tlie triumphs of tlic British engineer. 



It would be vain to expect that an annual meeting should ever recur with- 

 out the council having to lament the removal liy death of some who, by their 

 actpiiremcnts, or by their associations of friendship, were endeared to the In- 

 stitution. On the present occasion the council have to lament the death of 

 \o»r members, Mr. David Logan ami .\lr. Henry Ilabbciley Price, and of 

 your hoi\orary member, Mr. Davies Gilbert. The records of the Institution 

 contain several eommmiications from Mr. Logan, particularly one on the new 

 Graving Dock at Dmidee, and Mr. H. II. Price was, when in tow n, a constant 

 attendant at the meetings, and look a lively interest in the proceedings and 

 success of the Institution. Mr. Davies Gilliert was, by his writings and his 

 influence, a great benefactor of practical science, and the Transactions of the 

 Royal Society, over which he presided for three years, contain several papers 

 of great value to the practical engineer. lie took great interest in the in- 

 troduction of Mr. Watt's improvements in the steam engine into the Cornish 

 mines, and in the controversy betwixt Mr. Watt and Mr. Jonathan Horn- 

 blower respecting working steam expansively, the former employing one cy- 

 linder only, the latter two cylinders, in the manner afterwards revived by 

 Woolf ; the theoretical elKciency of the two methods Ijcing identical, hut 

 simplicity and mechanical advantage being greatly in favour of the former, as 

 its present universal adoption testifies. Mr. Davies Gilbert introduced into 

 jiraetical mechanics the term " efficiency" as the product of the applied force 

 ami of tlie space through which it acted in contradistinction of the term 

 " duty," as indicative of a similar function of the work performed. His at- 

 tention was also directed to tire theory of suspension bridges, when the plan 

 for making such communication across the Menai was submitted to the com- 

 missioners appointed by paiUament. It appeared to him that tlie proposed 

 depth of curvature of the catenai-y was not sntlicient, and his well-known 

 theoretical investigation of this subject was undertaken with the view of as- 

 certaining this fact ; and in consequence of these investigations, the interval 

 between the points of support of the chains and the roadway was increased 

 to the height which appeared to him requisite for works of this natm-e. The 

 labours of this distinguished individual for the |H-omotion of science were un- 

 remitting. He was the founder of several societies; he was the discoverer 

 and early patron of the talents of Davy ; and wliile in parliament he laboured 

 most assiduously in the advancement of all the public works. Regret for 

 such a man, exerting the power of bis mind so advantageously and through 

 so many years, must tlvvays he strong and sincere ; but having attained the 

 ordinary limit of human life, he sunk into the grave amidst the resjiect and 

 esteem of all who knew him, and has left behind him a name which will ever 

 bear a prominent place amidst the names of those whose lives and talents 

 liave beeu devoted to great aud noble purposes. 



GEOLOGICAL SOCIETY. 



On the relative Jyes of the Tertiary and Posl-Tertiary Deposits of tits 

 Basin of the Clyde, by James Smith, Esq., of Jordan Hill. 



Ill former communieatious Mr. Smith showed that deposits in the basin of 

 the Clyde had been elevated above the level of the sea during very recent 

 geological epochs, aud that some of these beds contain tcstacea wliieh indi« 

 cate the prevalence, during the period of their accumulation, of a colder 

 climate in Scotland than exists at present. In this paper he confines his re- 

 marks to subsequent observations, which afford most satisfactory evidence 



that these eouiparatively mailera deposits are divisaWe iutg two distinct 



formations, dift'ering in their fauna, and separated by a wide interval of time. 

 In the older of these formations Mr. Smith has found from 10 to 15 per cent, 

 of extinct or unknown species of tcstacea ; but in the newer only such shells 

 as inhabit the British seas. He accordingly places the former among the 

 newest pliocene or pleistocene deposits of Mr. Lyell, and the latter among 

 the post-tertiary series. Both of these accumulations, be, nevertheless, con- 

 siders to be older than the human period. In the lowest part of the pleisto- 

 cene formation of the basin of the Clyde, Mr. Smith places the unstratified 

 mass of clay and boulders, locally called " till," and in tlie upper, which rests 

 upon it, the beds of sand, gravel, and cliiy, containing marine shells, a portion 

 of which arc extinct or unknown. He is of oiiiiiion that some of the similar 

 accumulations in the basins of the Forth and the Tay, will probably prove to 

 lie of the same age, as well as the elevated terraces of Glenroy, recently shown 

 by Mr. Darwin to be of marine origin. He is also convinced that a very 

 great jiroportion to the superficial beds of sand, gravel, and clay will be as- 

 certained to be tertiary, although the absence of organic remains must rentier 

 it difficult to obtain, on all occasions, satisfactory evidence. During the post- 

 tertiary epoch, or while the beds containing only existing tcstacea were accu- 

 mulated, changes of level in the liasin of the Clyde must have taken ]ilaec 

 to the amount of forty feet; but during the human period no change appears 

 to have occurred. 



The paper concludes with a list of the fossil shells obtained by Mr. Smith, 

 and not found living in the British seas, or of doubtful existence in them. 

 The mindicr of the species is twenty-four — six of which occur in the crag of 

 England, three in the most recent tcrtiar-y strata of Sweden, and seven in a 

 living state in the North seas. 



On the noxious Gases emitted from the Chalk and ovcrlyinrj Strata in sink' 

 inij U'ells near London, by Dr. Mitchell. 



The most abundant deleterious gas in the chalk is the carbonic acid, and 

 it is said to occur in greater quantities in the lower than the upper division 

 of the formation. The dislrilmtion of it, however, in that portion of the 

 series is very unequal, it having been found to issue in eonsiderahlc volumca 

 from one stratum, while from those immediately above aud beneath none was 

 emitted. Sulphuretted hydrogen and carburctted hydrogen gases sometimea 

 occm- where the chalk is covered with sand, and London clay, as well as in 

 other situations. In making the Thames Tunnel they have been both occa- 

 sionally given out, and some inconvenience has been experienced by the 

 workmen, but in no instance have the ctfects been fatal. In the districts 

 where sulphuretted hydrogen gas occurs the discharge increases considerably 

 after long-continued rain, the water forcing it out from the cavities in which 

 it had accumulated. The paper contained several cases of well-diggers hav- 

 ing been sullbcated from not using proper precantions. 



The tables of the Meeting-room and the Library were covered with dona- 

 tions of specimens and books. 



Wednesday, November 20. 



Four communications were read. 



An extract from a letter addressed to Dr. Andrew Smith by Mr. A. G. 

 Bain, dated Graham Tomi, Cape of Good Hope, Feb. 2\sf, 1839, announcing 

 the discovery of the skull and piths of the horns of an ox in an alluvial de- 

 posit on the banks of the Jlodder, one of the tributaries of the Orange River, 

 and forty feet below the surface of tiic ground. The piths measured, in the 

 direction of their cunatnre, and including the breadth of tlic os frontis, 

 eleven feet seven inches, but it is calculated tliat about five inches had been 

 broken oft' each point. Their cu'cumference at the root was eighteen inches, 

 and tlie orbits are described as situated immediately under the base of the. 

 born. Other portions of the head, and five molar' teeth, were found at the 

 same time. 



On tlie Oriyin of the Vegetation of our Coal-Fields and Wealdeyis, by J. T. 

 Barber Beaumont, Esq. 



The author of the communication is of opinion, that the jilants discovered 

 in the coal measures were not drifted into large estuaries and there sunk, but 

 that they grew where they are found, and that the districts now forming our 

 coal-fields were originally islands. The principal objections advanced in the 

 paper, against the theory of the transportation of the plants by great rivers, 

 are, that such bodies of water would have requii-ed for then- existence exten- 

 sive continents, of which there .-ue no traces ; that, as the coal strata near 

 Newcastle are 380 yards in thickness, the depth of the estuary must, in that 

 case, have exceeded six times the mean depth of the German t)cean ; that the 

 formation surrounding the coal-fields are of marine origin, aud bear' no traces 

 of having been dry land at the same time the coal aud its associated strata 

 were accumulated ; and that the freshness of the plants is opposed to the 

 view of their having been drifted from a distance, and sunk in a deep estuary 

 — a process which must have been accompanied by a certain extent of decay 

 in the plants. Mr. Beaumont then briefly proposes the following, as a pre- 

 ferable theory to account for the production of the coal-fields : — He supposes 

 that they were originally swampy islands, on which plants flourished, and in 

 part decayed ; that the islands, during the settling of the earth's crust, were 

 submerged, and covered with drifted clay, sand, and shells, whicli buried the 

 plants; that these accumulations gradually raised the surface of sunken 

 islands till it again became dry land, and adapted for the growth of another 

 series of plants ; and that these processes were repeated as efteu as there are 

 alternations of coal and strata of earthy sediment. 



2 



