Biology and Geology
Classification of plants and animals.
Questioned the age of the earth.
For a good biography of Ray, see:
Duncan, J. 1835. The Natural History of Beetles. W.H. Lizars, Edinburgh.
Duncan, James. Edited by Sir William Jardine. 1845?. Naturalists Library Vol. XXXIII Entomology: Beetles. W.H. Lizars, Edinburgh.