I have often seen this book on amazon in the past and recently took up the chance to read it. I was very very suprised by how well written and good this book is. As he says at the start, there is no information in this book that hasn't been verified by himself and at least two other astral projecters on the astral plane, so at least you know this is not another theory book wrote for fun or giggles.
The chapter on some of the inhabitants of the astral plane is almost worth the price of the book itself.
My one or two wee niggles (there is always one floating about isn't there) is that I was unfamiliar with theosophical terms before reading this. So I found myself having to write down words and look them up later to make sense of some passages. So my copy has a handwritten glossary in the back few pages - which completely adds to the charm of the book for me personally. I now know what 'kamaloka', 'kaliyuga' and 'upadhi' means. So not really a negative niggle then. Another thing is the author is very pro-seance, as were very popular back in the day, and so I feel he goes to great lengths to almost explain and justify the seance going ons. Which to me, felt like a waste of 3-4 pages of an already short book.
So while my paragraph on my very slight negatives is seven times longer than my pros, I mean to say that this book will be on my 'favourites' shelf in my bedroom for a very long time to come. I encourage you to buy this.