""Snow, John (1813-1858)," "
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Power relied heavily on B. W. Richardson's truncated memoir of Snow, published in 1887; among other clues is the correct date of Snow's birth, which Richardson in 1858 had listed as June 15 1813. Hence, Power is incorrect when he wrote that the 1858 memoir was reprinted; the 1887 version is heavily redacted.
Power repeats some of Richardson's biographical errors (eg., that Snow's 1849 version of On the Mode of Communication of Cholera received a £1200 prize from the Institute of France). But it did serve for many decades as a short-list of highlights about Snow's life.