Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Sir Leonard Rogers FRS (1868 1962) was a founder member of the Royal Society of Tropical Medicine and Hygiene, and its President from 1933 to 1935.Rogers had a wide range of interests in tropical medicine, from the study of kala-azar epidemics to sea snake venoms, but is best known for pioneering the treatment of cholera with hypertonic saline, which has saved a multitude of lives.Rogers was one of the pioneers in setting up the School of Tropical Medicine in Calcutta, India.