There are valid issues with Lovecraft's personal views which I will not reiterate because they are well documented. This novella is somewhat longer than most of his other works. It has a very interesting premise, but has the major drawback of a slow, dragging, and overly detailed sci-fi element in the middle that seems like it could be about 1/5 the length it is. The beginning and end are mysterious and exciting respectively, and are classic HPL.