Dated 1909, this historic photograph depicted a portable emergency hypochlorite device that in this case, had been used to stop a 1914 epidemic of typhoid fever in Benson, Minnesota. Its purpose was to purify water contaminated with the pathogenic bacteria, Salmonella typhi. It was one of a series of instructional photos used by the Minnesota Board of Health to train public health workers.
The focus of the images, and the training effort was to promote sound practices involved in protecting potable water supplies from bacterial contamination. The descriptive information accompanying this image referred to a governmental publication outlining the operating instructions for this device. The specific citation was: “Whittaker, H.A.; Hypochlorite treatment of water supplies; portable plant and field equipment for its administration Public health reports, 30:608-18, 1915.