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    Jahhakx 2Q, 1855.] Tll/MASEB, *5

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    NEW METROPOLITAN COMMISSION OF SEWERS.—M...

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    Mr. Cobden At Leeds. On Wednesday Mr. Co...

    ** That , in the opinion of this meeting , the war in -which England « md France are new engaged with Russia is a great contest foreed apon then * by the outrageous a <* gressi < m of the latter Power upon the Turkish empire , and is intended to ereate a spirit of aggrandisement on the part of the Czar which , threatens the independence of other nations , and this meeting is of opinion that the war ought to be prosecuted with the utmost vigour until safe and honourable terms of peace can be obtained . " The following amendment was then proposed and seconded : —

    " That this meeting , without giving any opinion on the origin or conduct of the warr earnestly desires that the present negotiations for peace may be carried to a successful issue , and the further evils of a protracted contest spared to this country , to Europe , and to the world . " . The voting , however , was decidedly against it , and on the original motion being put very few hands were held against it .

    Jahhakx 2q, 1855.] Tll/Maseb, *5

    Jahhakx 2 Q , 1855 . ] Tll / MASEB , * 5

    New Metropolitan Commission Of Sewers.—M...

    NEW METROPOLITAN COMMISSION OF SEWERS . —MR . F . O . WARD'S STATEMENT . Having disposed o f those branc hes of the subject which relate to the collection of sewage in the houses , to its conveyance through districts of the town , and to its diversion by intercepting tunnels from the Thames , Mr- F . Q- Ward proceeded to state his views as to the policy which the Commission should adopt with respect to that much vexed branch of the question—the Agricultural utilisation of the sewage . The value of town refuse as manure , Mr . Ward said , had been ca lled in question very recently by no less an authority than Mr . Caird , who had distinguished himself as the agricultural commissioner of that able journal the Times . Mr . Ward thought ,

    however , that he could produce an overwhelming body of evidence , both scientific and practical , in support of the view adopted by his sanitary friends and himself , —that town refuse was one of the most valuable fertilising agents we possessed . To shorten his argument he would direct attention solely to the azotized ingredients of the sewage ; for though the phosphates , the potass , and the soluble silica of sewage were valuable , and ought by no means to be wasted , yet their value was insignificant as compared with that of its azotized or ammoniacal elements . Professor Way , the able chemist of the Royal Agricultural Society , —a man who had brought eminent

    ability to bear , with great success , upon subjects of the highest national importance—had illustrated the high relative value of ammonia by what might be termed a chemico-eeonomical analysis of guano . Mr . Way had shown , that of the total price given for , the _ best guano , at least 80 per cent , was paid for the ammonia in it . ¦" G " u ¥ nd ^ dntainefVl 6 '"p'er" < Scnt ;~ of ammonia , 24 per cent , of earthy phosphates * and 3 £ per cent , of patass ; the remaining 56 £ per cent , consisting of mere sand and water , which were not only wortlilesa themselves , but diminished the worth of the other ingredients , by diminisliing tlieir portability . Now , looking to the prices at which , these

    several substances could be procured in the market , it appeared that of 10 / . paid for a ton of guano , 8 / nt least were paid for the 336 lbs . of ammonia in it , and only 2 / . for the 537 lbs . of earthy phosphnte and the 70 lbs . of potass . It was clear , therefore , that , for all practical purposes , they might confine their attention to the ammonia of the sewage ; for if its Ammonia would not yield a ' profit , neither the phosphates , nor potass , nor anything else in it would . Now , on . comparing the various investigations that had been published , by Berzelius , Lecanu , Boussingault , Gasparin , Paulct , and others , as to the weight apd composition of human ro 3 ldua , lie found that an adult produced annually about 16 £ lbs . of ammonia , of which 4-5 ths , or 13 lbs ., were secreted by the kidneys , the remaining l-5 th , or 3 * lbs ., being

    contained in the more solid residuum . Children and old persons produced less ammonia ; but us the horses , cows , dogs , and other animals , in London yielded a large annual quantity , besides that which was produced by gasworks and other manufactories , he believed that it would be an undor-estimate to put the net produce , after all deductions had been allowed lor , at 15 lbs . per head of the population , taking 4- & ths as urine ammonia and l-5 th as fuecal ammonia . Now , amongst the many valuable experiments which had been made by that able and eminent man , Mr . Lawos , of Rothampatead , there was one that ; would juat servo to illustrate the value of the ammonia thus produced ,, every year , by each individual .. Mr . Lawes had put on a plot of cornland a quantity of eulphato of ammonia , corresponding to 14 lbs . of real ammonia ( the quantity was (] 5 jQ ) 3 . of the iuapura commercial sulphate ) and he had

    compared the produce of that plot with the produce of an adjacent plot' kept tramanured for the purpose . The unmanured plot produced 16 bushels of comthe manured plot 21 bushels j so that 14 pounds of ammonia , used as manure , had produced an increase of no less than five bushels of corn , worth , at present prices , he believed , about 40 shillings . The proportion of increase varied of course with weather and other circumstances ; but this result was rather below than above the average effect of ammonia on corn crops ; and on grass lands its influence was th But

    greater still , quadrupling e ordinary crops . he was content to take it that the average annual produce of ammonia by each individual of a mixed urban population would , if delivered to the roots of growing corn * produce an increased yield of five bushels of dressed grain . But he would now turn from physiological and chemical con siderations , and from experimental trials , to the rougher but not less reliable results of practical experience on a large scale . Take the Edinburgh meadows for example . Here was a case in which town sewage , very roughly applied no

    doubt , and without the necessary precautions to render the operation inoffensive , had nevertheless raised land of the most barren description—much of it , in fact , mere sea-side sand-hills—to such a state of fertility that 307 . per Scotch acre was paid for several portions of it ; and that the average rental was as high as 20 / . per Scotch acre . The yield of these irrigated sands was actually tenfold the average yield of agricultural lands in Great Britain . Look , again , at the sewage-manured meadows below Mansfield ; thirty years ago those meadows were a wilderness . —the higher parts covered with gorse , the lower levels a snipe-haunted bog . To these lauds—worth 4 s . an acre at the utmost—the town sewage of

    Mansfield had been conveyed by a dyke , and distributed by a system of gutters and sluices ; and what was the consequence ? They were at this moment producing no less than 12 / . 5 s . per acre per annum . This had been accomplished by a very dilute form of town sewage ; for the whole river ( the Maun ) had been diverted into the dyke , with the drainage of only that small part of the houses which had been as yet fitted up with water-closets .. " As these were multiplied the fertility of the _ irrigated lands below the town would doubtless increase : and

    it was satisfactory to find that these sewage irrigations were so rapidly absorbed by the land as to be imperceptible a few minutes after the water had been turned on , producing far less offensive smell than the ordinary top-dressings of farm-yard manure , which lay for days together , exhaling ammonia , beneath the sun . Sewage irrigation was practised with equal success , by very similar means , in many parts of the continent . The sewers ot Milan , for example , are discharged by a canal called the Vettabbia , which flows a distance of ten miles to the river Lambro , and irrigates in its course a considerable tract of meadow land . These meadows are every year four times mowed for stable-feeding —besides yielding three abundant hay-crops ( in June , July , and August)—and furnishing , in September , ^ p lentiful- * pasturage -for the cattle , till ... tlie

    winter irrigations begin . In all these cases , however , the sewage was distributed by open gutters —a far costlier and less efficient method than the distribution" through pipes with hose and jet now extensively practised in tliis country , which had the honour , he was proml to say , of having originated this plan . Already the sewage of Rugby had been taken on lease by an enterprising landowner , who had laid down pipes for its distribution over five hundred acres of land ; and who , it was stated , was so well satisfied with the result , that he was about to pipe five hundred acres more . . He ( Mr . Ward ) had no doubt that the produce of this land would be quadrupled ; and that the owner , who had got the lease of the Rugby sewage at an almost nominal rent , would make a fortune by his speculation—and a fortune ho richlv deserved for his

    boldness in leading the way . He ( Mr . Ward ) would therefore assume that the commission recognised the value of town sewage as a powerful manure , and he would come to the question how , under the circumstances of so vast a city as London , this valuable matter might best be made available . Two methods , they woro aware , had been proposed for this purpose—the moist and the dry method : the plan of liquid manuring na practised at the places just referred to , and the plan of precipitation , different forms of which had been proposed by Messrs . Higgs ,

    Wickstead , Stothart , Angus Smith , and other able and ingenious men . Each of these plans hod its advantages . Undoubtedly , if a precipitate , aa rich as guano , could be cheaply obtained from sewage , by some agent capable of throwing down the whole of its fertilising ingredients , such a product would have a high degree of practical . value , especially in the case of towns whose great size or disadvantageous position made it difficult to utilise the whole of their refuse on land in their immediate vicinity . On the other hand , the delivery of liquid manure by gravitation or steam power , through , pipes , obviated the

    expense of the precipitating process , and substituted the cheapest-known means of conveyance aad-distribution for * costly cartage and hand ; labour . His chief objection to the- precipitating * processes was , that no chemical agent had yet been discovered which would throw down alt the valuable ingredients of sewage in a fbrm sufficiently compact to come into eompetitkm with guano . . Messrs . Haggs , Wiekstead , and . SSothart all used lime as a precipitant . Dr . Angus Smith , an excellent chemist , and a gentleman for whom he had a great personal esteem , had suggested sulphite of magnesia ; while the Sewage Manure Company were producing a compost , which he believed had a ready sale , by filtering the Ranelagh sewer water through tanks filled with peat eharcoal . Now lime precipitated only that portion of the ammonia which

    was furnished to the sewage by the more solid ejecta ; instead of precipitating it disengaged and wasted the ammonia derived from urine . The reason of this was obvious . That portion of the ammonia which was derived from urine existed in sewage in the form of ammoniacal salts r and lime being an alkaline earth combined with , the acids of these salts , and set free their volatile base , of which part flew off as gas , and part was carried away in solution in the water . The fsecal ammonia , on the contrary , was in the form of organic compounds which lime could not thus rapidly decompose ; and these the lime entangled and took down in its descent , very much as white of egg clarifies coffee by entangling and Avithdrawing from , the liquorthe pulverulent matter in suspension . Unfortunately , the faecal ammonia was only 1-5 th of the whole , the other 4-5 ths being contained in the ammoniacal salts derived from the urine .

    The ammoniacal vapours given off it was proposed to condense , no doubty and some part of the wasteraight possibly be thus prevented ; but a great deal of free ammonia would still , he feared , escape in watery solution . The ammonia retained by the compost , moreover , would be so small a per-eentage , encumbered with so much comparatively inert lime , that five or six tons of the precipitate would be required to produce the effect of a single ton of guano . Hence fivefold car-fcage costs , and a proportionatcinerease in the lalw * - * f spreading it on the land . Mr . Stothart , beside"S * 'the lime , proposed to employ the sulphates of alumina and zinc , as well as night-soil burned to a sort of charcoal , in the hope

    of absorbing the ammonia disengaged by the lime ; but much would still escape ; and ^ moreover ^ a question of cost would arise , which , in dealing with , large masses of sewage , would , he feared , defeat the plan—full of . merit and ingenuity as it undoubtedly was . Dr ; Angus Smith proposed sulphite of magnesia as a precipitant of the ammoniacal phosphates of the urine ; and . these it would no doubt effectually throw down , as double phosphatic salts of magnesia and ammonia . But sulphite of magnesia could not throw down carbonate of ammonia , a salt which , unluckily for this plan , was fifteen times more abundant tlian the phosphate of ammonia in the urine . The plan of filtration through peat charcoal had been attended

    with some degree of success ; but there was reason to ^ . fe . ar _ tUatJthis ... agent ? i- lmving __ a rapid oxydising power in virtue of its porosity , must ; decompose " and ' waste a large proportion of the ammonia , though a certain proportion was certainly absorbed and ^ retained . Much depended on these proportions , which he had not j r et been able to ascertain , and which would be a very fit matter for investigation . Any sensible waste of ammonia or of the other valuable ingredients of sewage , would suffice to condemn the plan ; and such waste , he was afraid , took place to a considerable extent in tliis process as in all the other

    precipitating processes . 1 hen again it was to be remembered , that all these composts were to be used as ^ top dressings , and , like other top dressings , wouid be exposed to have their ammonia evaporated by the sunshine , or washed into the ditches by storms of rain ; wliile liquid manure was no sooner delivered than it sank dowu at once to the roots of the plants . Fertilising matters , they were aware , must be in solntion , in order to be available as plant-food ; and it dul not seem desirable to bo at great cost to solidify substances , which must be re-dissolved before the roots could absorb them . For those and other reasons ho

    looked forward to pipe distribution , as tho p erfect method which would ultimately prevail for tho utilization of the London sewage . The cost of pipage , with steam engine and pumps complete , allowing 7 £ per cent , for interest and maintenance , is only & 9 . per acre per annum ., and the average working expenses are rather loss ; so that tho outlayis amply reimbursed by the increase of the very nrsfi crop , Tho cost of brick culverts with branches to convey tho London sewage to farms so organised would also be inconsiderable , relatively to the vast increase in tho produce of the land , and to the cheapness of provisions which would thence etrtue . Quadrupled grass crops would enable double tho quantity of meat to bo raised on half the extent of lnnd and this would set free a vast breadth oi the soil for the growth of grain and rootu . This abundance of food would of itself remunerate the

• Citation
  • Leader (1850-1860), Jan. 20, 1855, page 7, in the Nineteenth-Century Serials Edition (2008; 2018) ncse-os.kdl.kcl.ac.uk/periodicals/l/issues/cld_20011855/page/7/