Letheby, Tidy, and the London Water Companies

The third great challenge to Frankland's water analysis came from a group of chemists employed by the London water companies as analysts, consultants, expert witnesses, and publicists, very much the sort of multiple role Pearson and Gardner had played in 1828 and Brande and Taylor in 1850–52. There was one difference: owing to

the establishment of the position of a water analyst in the Registrar General's Office the companies now faced continual scrutiny of their supplies. They therefore had need of their own analysts to ensure that the public's knowledge of the water did not come solely from some minion of William Farr, no friend of the companies. Among the companies' chemists were men of high reputation in the world of science (it was of course precisely that reputation that made them useful to the companies) such as William Crookes, William Odling, and James Dewar. Others, like Henry Letheby and Charles Meymott Tidy, were of lesser stature, yet willing to tailor their statements to the companies' needs, no matter how far this might depart from current scientific consensus.

The first of these regular analysts was Henry Letheby, medical officer for the City of London and professor of chemistry at the London Hospital. In 1856 Letheby had succeeded John Simon as medical officer of the City of London and continued Simon's policies. In 1861 he began monthly analyses of the water of the New River, Kent, and East London companies, and by 1864 he was analysing waters of all the companies. Letheby continued these analyses for the rest of his life (he died in 1876). Ostensibly they were sponsored by the Association of Metropolitan Medical Officers of Health, but the expenses of analysis were met by the companies. However 'uninspired' and 'plodding' he may have been as a sanitary administrator, Letheby the water analyst was outspoken and aggressive.^[43]

By the early 1860s Letheby had recognized specifically polluted water as a route of zymotic disease transmission and was campaigning to close the City's cesspool-polluted shallow wells. During the 1866 cholera he, like Frankland, found existing methods of purification and analysis inadequate. Even the best filtration would 'never be sufficient to . . . [secure] the complete removal of those subtle agents of disease, which even the most refined appliances of the chemist have failed to discover.' And worse, if living germs were responsible for cholera—and 'unquestionably' they were—oxidative purification, whether in rivers or by Condy's fluid (potassium permanganate), might not destroy these presumably resistant organisms. He was skeptical of chemistry: a chemist 'would be putting forth very dangerous propositions, . . . if by relying on his science alone he ventured to dogmatise on so difficult a subject.'^[44] His assessment differed from Frankland's in one striking particular however: whereas Frankland believed the water companies were distributing dangerously polluted water, Letheby believed contamina-

tion occurred in household cisterns, and was therefore the responsibility of the individual.

By the end of 1866 Letheby had begun to back away from the strong stand he had taken during the epidemic. He testified as a representative of the East London Water Company at several of the official inquiries on the epidemic.^[45] Letheby insisted that not only had the company's water not caused the cholera, but that its customers had possessed a 'singular' exemption from the cholera that surrounded them.^[46] Among his sharpest turnabouts was with regard to analysis. In February 1867 he affirmed that analysis did accurately reflect the sanitary quality of water.^[47] Since the water had been analytically good during the epidemic it could not have been the source of the cholera.

Through 1867 and 1868 the split between Letheby and Frankland widened as it became clear how pervasively Frankland was using his monthly reports to serve the cause of water reform. Letheby and others of the companies' allies were particularly troubled by the 'previous sewage contamination' calculation, which they rightly saw as a means of undermining public confidence in the water. In an attack on Frankland in the Saturday Review , PSC was described as 'an imponderable and imaginary element . . . entirely delusive.' Writing in the Quarterly Review , the engineer William Pole noted:

the companies complain, and we think with reason [that] . . . the Registrar's analysis [Frankland's] is calculated to produce needless alarm and groundless popular prejudice. . . . The prominent reiteration, month after month, of the terrifying charge of an enormous 'sewage contamination,' must produce an impression in the great mass of the public (who know nothing of the doubtful and disputed reasoning on which the statement is founded, or the far-fetched and metaphorical interpretation it is intended to bear), that it refers to some well-ascertained and offensive and unwholesome present state of the water.^[48]

From the presidency of the Institution of Civil Engineers, Thomas Hawksley likewise thundered against 'theoretical chemists' (Frankland) who used unwarranted phrases 'invented to frighten Her Majesty's subjects from the use of some of the purest and most harmless . . . of waters the world can furnish.'^[49]

Letheby took his stand against Frankland in April 1869 in an address to the Association of Metropolitan Medical Officers. His title was 'Methods of Estimating Nitrogenous Matter in Potable Water,' yet the focus of the address was his subtitle: 'On the Value

of the Expression "Previous Sewage Contamination," as used by the Registrar-General in his Reports of the Metropolitan Waters.' Coming slightly a year after the Frankland-Wanklyn clash of January 1868, the paper occasioned another round of heated discussion and editorials and letters to editors. Letheby recounted the enormous improvement in Thames water in the previous two decades. Organic matter had been reduced from four to six grains per gallon to about one-half grain. Yet 'great as the improvement is, the public mind continues to be agitated and alarmed by vague fears . . . unnecessarily excited by the persistent use of certain expressions of an improper kind by those who have taken upon themselves to report in a pseudo-official manner of the quality of the London waters.' As the 'custodians of the public health' medical officers should be particularly concerned about 'undue excitement and alarm of the public mind,' Letheby maintained.^[50]

In the discussion Frankland replied that he had not sought the position of water analyst, but otherwise sidestepped water politics to deal with the scientific issues at hand. He upheld the propriety of his analysis. Some standard was necessary to replace the unreliable incineration (ignition) and permanganate methods, he insisted. He maintained that 'previous sewage contamination' was now an empirically verified construct: nitrates, at levels greater than could be accounted for by rainfall, were found only in waters contaminated with sewage or manure. He was strongly supported by B H Paul and also by Charles Heaton, a medical officer, and J M Rendel, an engineer. But most of the meeting was sympathetic to Letheby, and to Wanklyn, though Letheby was pressed to explain his close relationship with the water companies.^[51]