James Dwight Dana FRS FRSE (February 12, 1813 – April 14, 1895) was an American geologist, mineralogist, volcanologist, and zoologist.

[3] He showed an early interest in science, which had been fostered by Fay Edgerton, a teacher in the Utica high school, and in 1830 he entered Yale College in order to study under Benjamin Silliman the elder.

In 1836 and 1837 he was assistant to Professor Silliman in the chemical laboratory at Yale,[5]: 7 [2] and then, for four years, acted as mineralogist and geologist of the United States Exploring Expedition, commanded by Captain Charles Wilkes, in the Pacific Ocean.

[4] His notebooks from the four years of travel contained fifty sketches, maps, and diagrams, including views of both Mount Shasta and Castle Crags.

Dana was the pre-eminent U.S. geologist of his time, and he also was one of the few trained observers anywhere who had first-hand knowledge of the northern California terrain.

According to Oliver C. Farrington, To SIT at the feet of Professor Dana and drink from the overflowing fountains of his knowledge, was a privilege which once enjoyed could never be forgotten.

Some examples of his teaching style were given by Oliver C. Farrington[8] The quality in an investigator which, other things being equal, he seemed to esteem most highly, was that of carefulness.

How often were his students advised to trust or to doubt the statements of an author according as he was or was not, in the opinion of Professor Dana a careful man.

One incident which Professor Dana used to relate to illustrate his teacher's fervor as a collector was that when on one occasion his little party had gathered at a remote place more mineral specimens than they could carry in their hands, the master, in preference to leaving any behind, improvised a bag from a pair of trousers and thus bore them safely to their destination.Dana died on April 14, 1895.