The cholera has wreaked intermittent misfortune and death upon large swaths of civilization. While its reach extends ever farther, engulfing new port cities and populations, we have come no closer to fathoming the mode of its communication nor to stopping this awful malady. The disease affects the alimentary tract first and foremost, which implies strongly that one should look to contaminated water or food to explain its transmission. Its epidemic spread is along the pathways of human commerce, but it spreads no faster than people travel. As it usually appears first at seaports, it would appear to be spread by mariners, but it only affects mariners sailing from cholera-affected ports. There are numerous examples of the cholera apparently being transmitted by consumption of water polluted by excreta. Nonetheless, the hypothesis that cholera travels through humans and especially through contaminated water has not been put to crucial scientific examination. Herein, the PI proposes to conduct that crucial study.