He halted a rabies epidemic that killed small children who played with infected mice, and he helped stop the spread of cholera in Japan.
Faulds became fluent in Japanese, and in addition to his full-time work as a doctor, he wrote two books on travel in the Far East, many academic articles, and started three magazines.
Whilst accompanying a friend (American archaeologist, Edward S. Morse) to an archaeological dig he noticed how the delicate impressions left by craftsmen could be discerned in ancient clay fragments.
The following month Sir William Herschel, a British civil servant based in India, wrote to Nature saying that he had been using fingerprints (as a form of bar code) to identify criminals since 1860.
Returning to Britain in 1886, after a quarrel with the missionary society which ran his hospital in Japan, Faulds offered the concept of fingerprint identification to Scotland Yard but he was dismissed, most likely because he did not present the extensive evidence required to show that prints are durable, unique and practically classifiable.
In 1922 he sold his practice and moved to James Street in nearby Wolstanton, where he died in March 1930 aged 86, bitter at the lack of recognition he had received for his work.
[4] The method of identifying criminals by their fingerprints had been introduced in the 1860s by Sir William James Herschel in India, and their potential use in forensic work was first proposed by in 1880.
Galton, following the idea written by Faulds, which he failed to credit, was the first to place the study on a scientific footing, which assisted its acceptance by the courts.