Letter (IMAGE) National University of Singapore Caption Darwin's handwritten letter to his former geology professor at Cambridge where he first mentioned his radical new book, On the Origin of Species Credit Reproduced with the kind permission of a private collection, USA, and William Huxley Darwin Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.