Harold Maxwell-Lefroy (20 January 1877 – 14 October 1925) was an English entomologist. He served as a Professor of Entomology at Imperial College London and as the second Imperial Entomologist to India. He left India after the death of two of his children from insect-borne diseases. He worked on applied entomology and initiated experiments on the use of chemicals to control insects. A formula he developed was utilized to save Westminster Hall from destruction by wood-boring beetles, while others were used to control lice in the trenches during the First World War. The success of his chemicals led to increased demand and the founding of Rentokil, a company for insecticide production. He was killed in an accident while experimenting on fumigants to control insects. Biography Maxwell-Lefroy was born in the village of Crondall, Hampshire, to Charles James Maxwell Lefroy of the 14th Hussars (whose grandfather was James Walker who had designed the Regent or Vauxhall Bridge in 1816) and Elizabeth Catherine, daughter of Alfred Henry McClintock, a Dublin surgeon. The hyphenated form Maxwell-Lefroy was adopted in 1875. He grew up in the family's Itchel Manor, on an ancient site which had once been property of the Bishop of Winchester. The manor itself had a long history, being mentioned in the Domesday Book, and filled with stories of ghosts and their hauntings (and demolished in 1954). As a child he was raised in an environment of opulence, with many servants at home to take care of the house and his needs. Education Harold was sent to school in Church Hill House in Crondall where one of his contemporaries, although a boarder unlike Maxwell-Lefroy, was Claude Grahame-White. He was later sent to study in Germany, and after returning to England in 1890 he was sent to Marlborough College where he was in Preshute House under master W.E. Mullins. Oddly he did not join the Natural History Society at school, contemporary members included William Keble Martin, Arthur Hill, and Lawrence C.H. Young (who went to Bombay in 1901 to work in a local business and also contributed to studies of the lepidoptera in the Bombay Natural History Society collections and died young in 1907). He finished school in 1895 and joined King's College, Cambridge, receiving a BA in the natural science tripos with first class in 1898. His specialization in entomology was influenced by David Sharp. He received a master's degree in 1902.