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area to which such a manure could be advantageously applied;for if the distance were great, the necessary outlay for convey-ance would form an effectual obstacle to its employment. Of asimilar nature to the last, is the objection which arises from theuncertainty of the demand; for in wet seasons, the manure inthis condition cannot be applied; and if at any time the soilbe supersaturated, the vegetation is supposed to be injuredthereby. Besides, if the sewage be allowed to remain onthe surface, it will emit very offensive and injurious odours,and become not only detrimental to the land, but highly dan-gerous to the public health.

To meet these evils, several methods have been suggestedfor precipitating the valuable portions of the sewage, and pre-paring them in a dry state for the "purposes of commerce,during which process the matters,are also de-odorized and dis-infected. It is a matter of dispute, indeed, whether the por-tions of sewage which are specially serviceable for agricul-tural purposes can be preserved in a dry form; but besidesthe evidence resulting from experiments with this form ofmanure, we have the favourable testimony of Liebig , whothus writes:—“Gypsum , chloride of calcium, sulphuric ormuriatic acid, and super-phosphates of lime, are substancesof a very low price; and if they were added to urine untilthe latter lost its alkalinity, the ammonia would be convertedinto salts, which would have no further tendency to volatilize.When a basin, filled with concentrated muriatic acid, isplaced in a common necessary, so that its surface is in freecommunication- with the vapours arising from below, itbecomes filled, after a few days, with crystals of muriate ofammonia. The ammonia, the presence of which the organsof smell amply testify, combines with the muriatic acid, andloses entirely its volatility, and thick clouds or fumes of salthang over the basin.” And in the quotation which we havepreviously quoted, the same chemist states his opinion, thatthe moisture may be removed without permitting the escapeof ammonia, and the sewage put into such a form as to allow itto be transported to great distances. In opposition to this,some persons have asserted, that where the smell does notexist, the fertilizing property has been lost; and others, thatalthough the offensive odour is got rid of, the deleterious pro-perties still remain. These opinions are indeed destructive ofeach other, and we are inclined to yield the greater amountof credit to Liebig ’s testimony. Mr. Richard Dover, whopropounded a scheme for disinfecting the London sewage,and preparing it for transport in a dry state, made some expe-riments upon sewage-water taken from the Northumberland-street outlet, in the presence of several persons competent toform a judgment on the subject, and who testify to havingbeen satisfied as to the success of the experiment. Manureprepared by this process has been experimentally applied toagricultural purposes, and, it is said, with very satisfactoryresults. Mr. Dover further proposes to apply the water,which is left, for the purpose of bleaching and other commer-cial undertakings.

Such are the statements with regard to the employmentof sewage-matters for agricultural purposes: that they areuseful fertilizing agents, there seems to remain no reason todoubt; but there still does remain a question as to whethersewage manure can be profitably employed for those purposes,considering the subject in the light of a commercial undertak-ing. Can it compete with other manures already in the market,or will the expense of its manipulation destroy its value as amarketable commodity? These questions still remain to beconsidered; for although the subject has been some yearsbefore the public, the evidence in favour of that manure isnot sufficiently decisive to justify its use on a large scale.

Now the very first principles of drainage depend upon the

resolution of such doubts; for if the sewage-matte 1 tothus employed, we should adopt a very different s .^ tl*®that which would be adopted, had we solely to get r ^. tr eo 1 'noxious refuse. There would be also a difference yas

ment, according to the condition in which the m a o® 6

to be applied, whether in a wet or dry state; f° r .case we should be tied down to the most economic ^ ei n5

of distributing it over the surrounding country ^ 01 it-

of pipes, and should have to regulate our levels " f ®lets accordingly; whereas, under the latter cond ^j n o- su c ^should be left at much greater liberty in arran D °preliminaries. (wr9 as

In the first place, if we treat sewage matte^ oe & todeleterious to public health, and incapable of being . p aIiaany useful account, we have to deal with a veiy r gjpiptesimple question ; our sole object is to get rid of ]t - , g py n<>however, as may be the object to be attained,means easy of attainment; and of the two cases, ca nD atbably the most difficult. We are well aware tba co01 pose“<annihilate the elements of which the matters ar ® jjjnati 0119 ’however much we may be able to alter their co ^ rant ;ng>and perhaps destroy their characteristic qualities- re rao' ie< *’then, that the noxious properties of the soil can ^ an( j th erlwe find two courses open to us, either to disinfect 1 ® r

dispose of it in any manner most suitable to ihe ^ [0ta hu a > aaelse to remove it, in its primary state, to a distance jjsinf eChabitation. If we adopt the former course, we ® g 0 ]l e ct 11 ^

it either during its passage to its outlet, or may^ ^ a(ur e

various streams into one or more reservoirs, a® j t; aft®the locality may render advisable, and there a ! n oS jng * Lwhich there will probably be no difficulty °f .g.gtrea 01 ’ ^either by conducting it into a river or runnl ] ape may sU ? eby some other means which the nature of the p • ha'

gest. If the latter expedient be resorted to, w ^ n scnr® e 'much greater difficulties to encounter, for we j a nd ft 11 !consider it inoperative for evil, until it 1® sa .•L ( j at *!launched into the wide ocean ; until it has ar * gnce . ^. c lpoint, we are not secure against it® fatal m t t kehowever, is no easy matter to accomplish: to e c j, a nneli ^in view, we instinctively look for some . natu , ia p0g ed d estin 0 rmeans of which it may be conveyed to its P'°P. a s tre a ® . p

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tion, and this is presented to us in the s j ia P*L an g, 0 n

river ; to conduct it to the sea by artificia ^ quest^^pt

the

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majority of cases, be entirely out o

account of its enormous expense; we nias ntv!11 . e that ^ t0the river as a last resource,objectionable on many accounts ; but i

get rid of the offensive matter, we wou

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method of effecting this object remains open gjj-cum 3 '" r ythe question will arise, as to whether under sue be ^ (l .

the sewage ever reaches its destination; an th^or^edifficult to answer positively that it does, an re> a n<l ^j, er e

bly we must rest content with a palliative me or jy. te i

it from the more densely populated i ISt thi C smaybe ed c on'there is a good river, not a tidal river, - ver willreadily, for the sewage discharged into t >e ^. ( ] l0U t in®

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veyed with its waters in an onward couisetion, depositing probably some of its l ieaV i an <rerouS- , fornot in such large quantities as to become .» alter®’tidal river, however, the state of the ca -j e jn ®jiS'

although we have the advantage of the e rres pott^ ,J>0

the refuse towards the sea, we have the c 0 f

advantage of the flow bringing it back a S a * t | ie dr a ' n . alI rsIt has been suggested with reference 0 nly " t jje

London by the Thames, that as the now > ^ (fiat fI _ ,, rl -sduration, and the ebb of 7, and that ^heref®’ 6 a P °range of flux is 7 miles, and reflux 10,