An Essay on the Material and Spiritual Universe, by Edgar Allan Poe.
Quickie recap: Actually, the title says it all.
Quickie review: Although Poe postulated these scientific theories purely from "instinct", many of them astounded scientists by proving true - in fact, he predated the big bang theory by 80 years. Because Poe operated by intuition, he considered this masterpiece to be a work of art, a "prose poem" rather than a scientific paper. No matter what you call it, it provides fascinating insight into the mind of the man who came up with so many top-notch macabre stories.
Quickie recommendation: For those with a morbid fascination of Poe.