September 8, 1854: Dr. John Snow removes the handle of the Broad Street water pump in London, effectively halting the cholera epidemic. He had mapped the outbreaks and suspected that the pump was the source of the disease vector.
September 10, 1984: Englishman Alec Jeffreys discovers DNA fingerprinting in Leicester, England. X-ray films of his tests first revealed the possibility of using DNA as a base for biological identification since every person has a unique DNA profile. Jeffreys made the discovery as an accidental outcome of research he was conducting to trace genetic markers through families for the purpose of understanding inheritance patterns of illness. The technique has since helped in forensics, crime investigation and identifying family members. The first use of DNA profiling in criminology in the Enderby double murder proved the innocence of a man who had confessed to the murders.
September 13, 1833: the first imported shipment of ice arrives in Calcutta, India, from Boston, Massachusetts in the specially insulated hold of the Clipper Tuscany, which had sailed on 6 - 7 May 1833 with 180 tons of ice.