The two "fathers" of modern geology lived during the
16-1700's
17-1800's
18-1900's

17-1800's 

I know that James Hutton is considered a father of modern geology and he was born during some where in the 1720's so that's the closest answer, also Charles Lydel was born during the late 1790's. 

It is useful for historians to write narratives so that history can be passed on from their point of view.  think about a story being told in third person, then think about it again being told in first person, by someone who actually experienced the event.