+-----------+----------+-------+-----------+ | | | |Deaths per | | |Population|Deaths | 10,000 | | | | |Inhabitants| +-----------+----------+-------+-----------+ | Hamburg | 640,000 | 8,605 | 134.4 | | Altona | 143,000 | 328 | 23.0 | | Wandsbeck | 20,000 | 43 | 22.0 | +-----------+----------+-------+-----------+ That infectious matter was communicated to the Elbe water from Hamburg is not in any way a hypothesis. Cholera germs had been as a fact found in the Elbe water. They were found a little below the place where the Hamburg main sewer flows into the Elbe. They were also found in one of the two Altona basins into which the water flowed before filtration." No more striking example could be found, demonstrating on a large scale the efficiency of filtration as a preventive of water-borne diseases than that of the cholera epidemic of Hamburg in 1892, yet, at the present writing, there are people holding public offices throughout the United States who do not believe in the value of filtration as a public prophylactic, or who are so indifferent as not to advocate its adoption. Nor is this disbelief confined to public officials; many there are outside of public office who have made no study of sanitation and cannot believe that merely passing water downward through sand will purify it, and for the benefit of those who wish to be better informed, the story of the Hamburg epidemic of cholera, together with the part played by filters in saving Altona from a worse visitation, cannot be too often told.