What is the author's tone in The Voyage of the Beagle by Charles Darwin?

Darwin writes in a distinctly British and classically trained voice. He favors long complex sentences mortared together with semicolons and colons, a habit he probably picked up in academia. The style makes the prose heavy and at sometimes obscure, with the meaning buried beneath verbiage. To the modern reader the book offers less entertainment value than to a 19th century reader, and thus requires more effort.