I really didn't like this book. At first, I thought it was because of the style of writing. This book was written in 1798, and it is a little difficult to get used to some of the conventions of that time period. But that wasn't it. Even excusing the writing style, I didn't like this book.
I didn't like the characters at all. Clara Wieland and her family all struck me as bored young men and women with nothing better to do than sit around gossiping. The "villian" of the piece, Carwin, reminded me of many of the villians in real life today who claim "It's not my fault. I couldn't help myself". He spent three chapters explaining how he just couldn't keep from using his "evil power" and came off sounding like a whiny adolescent.
But, worst of all, this is a book where NOTHING happens. The reader isn't shown anything; we're told the whole story. And, there's no indication of the "invisible power and nameless fear" mentioned on the back cover. There's just nothing spooky or suspenseful about this story.
I found the biography of the author from the 1856 Cyclopedia of American Literature, included in this volume, much more interesting than the novel. It seems Brown was quite prolific; as Wieland was his first published novel, it would be interesting to see if his later works improved.