The first recorded sighting of the lake was in 1870 by Mr. Watt and Dr. Nicholls, two Englishmen working in Dominica at that time. In 1875, Mr. H. Prestoe, a government botanist, and Dr. Nicholls were commissioned to investigate this natural phenomenon. They measured the water temperature and found it to range from 180 to 197 °F (82–92 °C) along the edges, but could not measure the temperature at the centre where the lake is actively boiling. They recorded the depth to be greater than 195 feet (59 m).