Very satisfying. Recognized it as soon as I saw it on Internet Archive. From 1984, read and re-read this a few times and was helpful in a few science papers, including one I did on black holes that I was proud of in 10th grade — right around the time Hawking made “A Brief History of Time” — but my library didn’t have that yet.
And… I never heard of Steven Hawking until AFTER I did my high school black hole research. This book didn’t mention him. Two encyclopedias in my public library didn’t mention him, neither did the set I had at home.