]830.] 



THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



.311 



PROCBSDINGS OF SCIBNTIFIC SOCIBTIES. 



INSTITUTION OF CIVIL ENGINEERS. 

 April 30. The President in the Cliair. 



E. Cottam was elected a Graduate, J. Dodds and E. Crcssy were elected 

 Associates. 



A paper was read " On Ihe Supply of Water from Artesiau Wells in the 

 London Basin, with an account of the sinking of the Well at the Reservoir of 

 the Neir River Compani/ in f/ie Hampstead Road," by R. W. Myln'e, which 

 was given iu the last Journal. 



lu March, 1835, an excavation, twenty feet in diameter, and twenty-three 

 feet deep, was made ; tlie sides were supported by wooden curbs, with puddle 

 at the back, so as to shut out the land-springs. A brick shaft was then 

 carried uji to the surface of the ground, and the excavation was continued for 

 fifty-nine feet tlirougli clay. The brick shaft was suiiported at every ciglit 

 feet by rings of greater exterior diameter than the shaft, so as to project a 

 few inches into tlie clay. Three sets of iron cylinders, eacli of less diameter 

 than the preceding, were introduced, as the unequal settlement of the ground 

 rendered it impossible to sink the preceding set any fm-ther. By means of 

 these, the well was simk to the total depth of one lumdrcd and eighty-three 

 feet. The canties formed at the liaok of the cylinders by tlie pumping out 

 of the sand, caused such extensive settlements, that the works were stopped, 

 until the jilan of continuing the sinking with the water in tlie well was 

 adopted. To this eomnumication was appended a report from Mr. Simpson, 

 in which he details the ditlienltics winch had been met witli, and particularly 

 the extensive sul)sidenee of earth causc<l by tlie removal of the saud. Tliis 

 far exceeded tlie quantity due to the contents of the well at the lower sand 

 stratum, and the subsidence proceeded most rapidly when the water was 

 pumped out of the well. The experience of wells near the metropolis shews 

 that tlie springs in the chalk are much more alnuidaut th»n in the saud, l)ut 

 in order properly to avail ourselves of these, there must be adits driven to 

 unite the water from tlie fissures in the cavernous structure of tlie chalk. 

 Tlie report proceeds to speak of certain methods of securing the present 

 works, and of prosecuting them, by either driving an iron pile curb, or sink- 

 ing iron cylinders east in entire circles. The former cannot lie reeommended, 

 as a considerable further subsidence would lie the consequence, and the 

 shaking of the ram would endanger the works. The latter is jierformed with 

 common boring rods and tools, the shells or Inickets are fitted with valves 

 opening upwards, and the material is raised by tlieui witli the greatest ease. 

 \\nien the cylinders become set, or when they do not sink in lu'oportion to 

 the material removed, they are sliglitly jarred by a heavy sledge hammer. 

 The advantages of keeping the water in equilibrium inside and outside the 

 cylinders is very great, and the method has been in many cases most sueeess- 

 fnl. The paper was accompanied liy a section of the works and the strata, 

 a nd by drawings of the various tools employed, 



May 7. The Puesident in the Chair. 



J S. Russell was elected a Graduate, and II. C. Bingliain an Associate. 



" The Sewage of the City of Westminster described and delineated," by 

 J. E . Jones. 



In tlie earlier statutes and wTitings on this snlijeet tlie word sewage, or 

 sewerage, is identical with drainage, as appears particularly from the act of 

 Henry the Eighth, which is the general Sewage .\ct by which the Commis- 

 sioners of Sewers are now guided, being for the most part applicable to fen 

 land drainage. The nietropoUs and ailjaceiit districts, comprehended witliin 

 a distance of ten miles from the Post Office, are divided into seven distinct 

 and independent trusts, whereof five are administered by local acts, tlie other 

 two liy the general Sewage Act first alluded to. The sewers falling into the 

 Thames within two miles of London, are, by the 3rd of James tlie First, 

 ]ilaced under the Commissioners of Sewers, and the 4rtli of George the Third 

 defines and declares tlie powers given by tlie act of James. Tliis statute, 

 passed in 1807, was not acted on to any extent fill 1813, tlie interval being 

 employed liy tlic commissioners in requisite arrangements. The priiieijiles of 

 drainage, or conducting the superfluous waters to their proper outlets, are 

 few and simple ; but in the drainage of a town, tlie masses of liuildings of all 

 ages and all kinds of various levels, tlie coneeiitrated mass of tilth and the 

 numerous conflicting interests, conspire to make the establishment of an effi- 

 cient system of sewage one of the most difficult, as it is one of the most jm- 

 lO'tant, obje.ti to which the skill of man can be directed. One great 

 difficulty has a'iscn fromthc eommissioners not being invested wiih powers 

 enabling them to originate new lines of sewers, but being confined to im- 

 proving those that exist, and eontroUiiig the eonstriiction of new ones. A 

 large portion of Westminster is below the level of high water, and the drain- 

 age of buildings being optional on the part of the builder, there consequently 

 exist insulated houses and (Ustricts of Kiatlisome filth for want of sufficient 

 compulsory powers on the part of the 'eouiniissioners. The obvious rcniedv 

 for these evils is, to give powers to the Conimissiouers of Sewers within their 

 districts to compel every person to drain bis pro|icrty in an etfeelive manner 

 under their appro, al, and to form such new main lines as ch-cumstances may 

 render necessary, and to imiiose general rates for their maintenance. A large 

 plan or map was exhibited of the city of Westminster, compiled from original 

 iiurveys in the possession of the Cummissioners of Sewers, and laid down" to a 

 iCa'e of one inch to two hundred feet ; the boundaries of the city and of the 

 several parishes, of the main lines of sewers, and of the collateral sewers. 



were marked with dillcrcnt coloured lines ; .also a Hook of Sections, consisting 

 of more than one hundred sheets of tables and drawings, showing the dis- 

 tricts drained by the main sewers, plans and sections on an enlarged scale of 

 all the main sewers, with the elevations of their several outlets or falls into 

 the Thames. 



Professor A\'allace exhibited a pentograph of a novel construction, by which 

 drawings may be copied or reduced and etched with great facility. Mr. Mae- 

 neill bore testimony to the .advantages of this coustriirtion over every other 

 which he had seen, and stated that he had been enabled to finish a plan in 

 three hours and a-lialf, which could not have been done by an ordinary pen- 

 tograph in less than twelve hours. 



May 14. The Pbe.sident in the Cliair. 



The Right Hon. the Earl of Orkney, and E. Lomax, were elected .Vssociates '■ 

 anil W. Tookc, as an Honorary Member. 



" .-/ Des ri/ition. of the Cnffre Dam round the thirteen and fourteen feet 

 piers of Wes/ininnlcr Bridge," by Lieut. V. Pollock. 



It was the inteutiou of Labelyc, the builder of Westminster Bridge, that 

 none of the foundations of the piers sliouhl be at a less dc]it!i than five feet 

 below tlie surface of the bed of the river, but the etl'eet of the removal of 

 old London ]5ridge, and of the increase of the average ditl'crenco between high 

 and low-water, had in 1836 lowered the bed near the pier, on the eastern side 

 to within eighteen inches of the platform, being three feet lower than in 

 1829 ! and but for the works done under Jlr. TeUbrd's direction by Mr. 

 Swinburne, and those which are now going on under the direction (if Mr. 

 M'alkcr and Mr. Burges, the piers would have soon become undermined. 

 Labelye is supposed to have been deterred from attempting to lay the foun- 

 dations by a eoftre dam, from the difficulty of keeping it dry and of reaching 

 the bottom ; this is, how"ever, now shown to be a groundless alarm, as one 

 has been constructed which is so tight that two men can keep it perfectly dry. 

 The cofi're dam, the construction of which forms the subject of this eomiiiu- 

 nication, is formed round the thirteen and fourteen feet piers at the west end 

 of the bridge, for the purpose of securing the foundations and repairing the 

 damaged arch stones. Previous to the commencement of the work fender 

 piles were driven ten feet into the bed of the river, and are five or six feet 

 liigher than Trinity high-water mark ; a trench was then dredged in the in- 

 tended line of the eoftre dam to the level of the highest caisson ; the first 

 guage pile was driven on the 14th of July, and the first sheeting pile on the 

 24th, and the water stopped out, or the eoftre dam completed, in the short 

 space of seven months. The author details the dimensions of the timbers 

 and the construction of the various parts of the dam, as represented in the 

 drawing accompanying the communication. There arc about 40,000 cubic 

 feet of timber in the dam. The mean depth of the mud in the dam, the 

 water being let out, was from four to five feet; underneath the mud, at 

 about three or four feet above the caisson, is a stratum of red gr.avcl of an 

 average depth of fifteen feet, and below this is clay. The weight of the piers 

 has bent down the caisson (as shewn in a drawing), but the timbers are still 

 sound and good. The pressure against the dam, .at an average high tide, is 

 l,77o tons. 



The President rennarked that there was frequently consideralile ambiguity 

 iu the use of the term ?■;>? of tlie tide, and miseoiiceptiou as to the effect of 

 the removal of old London Bridge upon the rise and fall of the tides. The 

 water falls lower by three or four feet, that is, by the height ol the sill which 

 was removed, but the difference of level of high-water is very small, no* more 

 than a few inches. The old London Bridge caused a sort of weir, varying 

 from eight to eighteen inches, as the water ran up, but depending in a great 

 measure on the quantity of upland water which was coming down, ami some- 

 times there was scarce any difference of level on the two sides of the bridge. 



The following premiums have been awarded by the council of the Insti- 

 tution of Civil Engineers during the present session : — 



-V Telford Medal in silver and 20 guineas to John Edward Jones, for his 

 pajicr and drawings on the se•^^■age of Westminster. A Telford Medal in 

 silver to Charles Hood, for his paper on w,arniing and ventilating buildings. 

 .\. Telford Medal in silver to Charles Wye Williams, for bis iia|icr on the pro- 

 perties and applidation of turf and turf coke. .V Telford Medal in silver to 

 Edward Woods, for bis paper on the forms of locomotive engines. A Tel- 

 ford medal in bronze and books suitably bound and inscribed, to the valtie 

 of three guineas, to Lieutenant Frederick Pollock, Bengal Engineerst for his 

 descri))tion and drawings on the cofl're dam at Westminster Bridge. A Tel- 

 ford Medal in bronze and books suitable bound and inscribed, to the value of 

 three guineas, to It. W. Jlylne, for his coinmimicatioii on the well sunk by 

 the New River Company, at their reservoir in the Hampstead Road. .\ Tel- 

 ford Medal in bronze, and books suitably bound and inscribed, to the value 

 of three guineas, to John Biilih-y Redman, for his description and drawings of 

 Bow Bridge. 



The following are the subjects announced for Telford premiums for the 

 ensuing year': — 



1. The nature and projierties of steam, especially with refercuce to the 

 quantity of water in a given bulk of steam in free eomnumication with 

 water at difierent temperatures, as deduced from actual experiment. 2. .\n 

 aecoinit and drawings of the original eonstrnefion and present state of the 

 Plymouth lireakwater. 3. The ratio, from actual experiineiit, of the velocity, 

 load, and |)ower, of locomotive engines oii railways: 1st. Upon levels; 2nd. 

 Upon inclined planes. 4. Drawings and description of the outfall of the 

 King's Scholar's Poud Sewer, and of other principal outfaU:i flf the AVcstmii), 



