 In 1899 Wright requested that Douglas accompany him to India for the investigative research of the first Plague Commission.On 31 March 1899 Douglas and H. J. Walton (at that time a lieutenant) were sent to investigate plague in the Garhwal District and other areas of the Kumaon Division of the United Provinces of Agra and Oudh.Their investigation lasted about 5 months, during which Douglas suffered from recurring episodes of malaria.