The Sentinel is collection of Science Fiction short stories was originally published in 1983. I’m sure I read it then. I recalled most of the stories. Recently, I got interested in the idea of “2001” that I might read the entire series, so I start with the short story that inspired it: “The Sentinel”. Once I finished that story I decided to finish the book. The stories date from 1946-1955; one from 1964 and one from 1971. Clarke is one of my favorite authors and this is a fine collection of his early short stories. What I find most interesting about this collection of stories is how many became longer works.