Adding this title to the app that I use to track my reading, I discovered that this is my first-ever story taken from an issue of
Amazing Stories
— believe it or don't.
I give this one four out of five stars, because it alternates between really good and laughable. Coming thirty-four years after H.G. Wells' War of the Worlds, it really felt like Tanner was borrowing two of the worst conceits from that tale, one — that aliens would drink human blood to sustain themselves, and two — that diseases would be able to transfer between races born on different planets. I was also appalled by the character design of the aliens. Ten-legged spiders with human heads? Now the alien concept was something I would have preferred Tanner steal from someone else. Finally, I thought the names for the characters was pretty comical. How does everyone pronounce the title character's name, 'Tummi-thak' or 'Tummit-hak'?
Other than that, I was pretty impressed. There was good character development, pacing, action and other thoughtful SF aspects that I thought were effective. Like the fact that Tumithak suffered from Agoraphobia when he got to the surface, and his reaction to the trees and grass. I can see why the young Isaac Asimov was impressed by it. His review is more succinct than mine.
He described it as "far and away the best and most exciting story I had ever read up to that time. I found the characters human and the hero all the more admirable because he could feel fear. I found the plot exciting and a deep humanity in the sentence 'Tumithak had to learn that in no matter what nation or age one finds oneself, he will find gentleness, if he looks, as well as savagery.'" Asimov also credited 'Tumithak of the Corridors' for inspiring his own description of the underground city of the future in Caves of Steel.