How do Walton's letters illustrate the tension between eighteenth-century rationalismand nineteenth-century romanticism?

Shelley's entire novel revolves around Walton's letters to his sister. Regardless, he is far more than simply the frame around which the story is written. Walton's character provides Shelley the opportunity to infuse a bit of realism into a story otherwise based on fantasy.

Walton is pragmatic and practical; he is also well apprised of the facts. On the flip side, he's an adventurer and a romantic. He symbolizes scientific advancement and exploration (19th Century) ......... but he is also the epitome of a romantic adventurer (18th Century).