WATER SUPPLY.

Otago Daily Times, Issue 285, 18 November 1862, Page 5

WATER SUPPLY.

(To the Editor of the Daily Times.;

Sir, S'ould you think the enclosed extract's (from '• Chambers Information,') on the supply of watr, of (sufficient ituponance to bring under the public notice at the precc-nt monnnt ; you will, I have no doubt, confer a ks-ting benefit by Vivi.-g- th.-sra a sp-ice in your valuable columns, that such facts may be generally known.

Organic nmite.r in aputrifyingstate formsth^wmrst kiuu if coiitamination that water can have. Tnough we may n«,t know the precis effects of these ;m----puritiiaou theaniinal system, the .-ii.gl- fact ot th ,r rendering t'ne water repulsive to the taste, und nauteous to the stomach, would be sufficient to condemn tneir use; what is d :/mre» alile to the senses, must be presumed to be. unwholesome in addition until the con trary is proved.

Thtufih no one has ever pone the lenfr'h of maintaming-, as a general truth, the wlio.'ewmi ness if water abounding in vegetation, insects, and decaying matter ;>et the waters of the Thames, tv.-n wjthin the influence of tlie tides, when; ir. is con ram in ate i b\ the whole sewage of the m^troj-olis, found defenderf.- until lately,on the plea that the amount of irepi.nty was too sinnl) to liHim

"As to tl.is plea of sma'ln. ss of amount, the highest mf-dical authonties ho! d that it is ing o^sible to say »«■ w-Miail a quautity if oiganic waiter in n state of ienoentati.n may not do harm. '1 he powerful effects of vaccination are produced by an a in.,st imponder abe quantity of organic vaccine matter.

" We are nc-t, however, loft m< rely to presume that organic impurity in w;.ts ris pr. judicial to hi ahh Ata meeting of tha Socittyof Aits, Lo< don, 1856, when the whole question oi water sapjly was ciscussi-d, the Hi»nu>an adduced the following striking f aC ts :— 'He would quote to tiiera the- n suits ot a gigantic exper metit which ha<l been undesignedly cwductfd on half a million of human beings, and wii.ch would s-efc this fact in a stiong light. "It happened that in the last epidemic of cholera, a certain haii million of population, dwelling contiguously over one large area, were drinking different waters, .some from private wells, but the larger number • about four-tilths of the wl oli—from two commercial sui plies. There \v. re the mains oi two rivol water companies going thn tub. the dis•nct. often litera ly s !d ■by side; one c< m^uij- supplying- 2 ; ),000 houses, the other nearly 40,000; so that in this vast experiment tlier -. weie i.nmense nm^es ofj'opu'ationhviij", as far as could lejudged, in all res pects a;ike. except as to the o: c "if er nee o their wav r supply only. And that diitero-nce was that one c>mpa: y diew it* water from buh up the rJ names, where I it was of comparative excellence, while the oiher drew iis water from low dorm the river, where it was profusely contaminated with town drainage. Among thr population to wbi-b he alluded, there were in 18534 more than 4 000 deaths from cholera; and whrn the • pidemie had subsided, an inquiry was made," house ty luuse, astothosedo.ths, and as to the water supply of the several houses where they had occurred. The inquiry was conducted with every precaution, to tmad sources of fallacy; arid the n suit was this :— In the one set of h. u«s, the mortality of the population wa- 37 per 10.CCO, ai:d in the other stt of houses ir was 130; that is U> say, the cholera death rate was 3£ times as prtafc in the one as in the other. It also fortunately happened in this very decisive case, tha^ further information cou:cl be procured, &o as to pr« sent almost a duplicate ex- i penment. 'J h<> returns of the Registrar-General had n-ade it pcs ibJe to ascertain the mo: tality during the pieitding epid'-mic of cholera, that of 1848 and 18J9. Going bark to that period, ir. was found that the mortality from cholera was a> out equal in the two groups of houses.. The mortality ier l(»,000 of population was in the one case 12\ and in tMe other UH. The tenantry wh;ch in 1853 and 1854 suffered a death rate of only thirty-seven, had in 1848 and 1849 suffered a death rate of 125; and why? At that time, instead of drawing a comparatively pure supply f-oui high up the river, it was drawing from nearly tne same source as that other company which, on the late occasion, contrasted so unfavourably with it. Now, these unintended experiment had been on so large a scale that they niiirhr \ c considered conclusive ; and as the drnVreuce between the two waters in question, wa>> only thrt one of them contained a large admixture of town d ainage, they might Le eoi>*i>'errd to establish the e>treine]y dangerous tendency of this contamination, during the periods ef choli ra. Among the population sup,; ied with ibul water, the deaih rate was3^ times gr ;ter tl an among those who bad a n.ore ■wholeicmj supp'y.'! -~-,.... I s sk. such of your readers as feel an "n^erest -'n our sanitary nieat-iires,'to weigh these fac s, the"reasons are obvious. —I remain, sir, ' " ' " Yours obediently, _ £i>W4.iti> Simpson. Drniedin, ' ; ' November 15,1862.