Instruct: Classify Amazon reviews into positive or negative sentiment
Query: A Classic that holds up well

For a book over 70 years old, I was very impressed with the story. There was action and adventure from start to finish which was not hampered by how old the book was. However, this was originally a pulp novel, and it shows. Don't expect be made to ponder the complexities of life or the nature of good vs. evil. This book was written for enjoyment only and science fiction fans should be able to appreciate it for what it is.