Rather abrupt changes with little to no flow between them, although the anecdotes themselves are fine. It wasn't quite what I was expecting; I had assumed the "other essays" mentioned were essays about writing, when in reality they were just whatever Twain had thought of at the moment, including his views on ESP.
This makes sense, however: at the time this was published, Twain was going completely bankrupt. He was churning out piece after piece to make ends meet, these essays among them. The diminishing quality truly does show.