Principles of Geology: being an attempt to explain the former changes of the Earth's surface, by reference to causes now in operation is a book by the Scottish geologist Charles Lyell that was first published in 3 volumes from 1830–1833.
Principles of Geology: being an attempt to explain the former changes of the Earth's surface, by reference to causes now in operation adalah sebuah buku karya geolog Skotlandia Charles Lyell, yang pertama kali diterbitkan dalam bentuk 3 volume pada 1830–1833.