Book called Darkness?

[hermit]

Hi, I am looking for the author of a Book that I think is called Darkness. I read it back in the 70s or early 80s which I would really like to read again.
The story is about a race of people who live underground in tunnels. They use stones to create echos in the tunnels and caves which they use to be able to effectively see where they are going in the darkness. I think all the names of the people in the book were all normal and reverse, e.g johnnhoj
towards the end of the book one of them finds light, exiting the tunnel and meets an above ground human.

any help with finding this book would be a great help.
many thanks

[lolrus]

I'm sure that's "Dark Universe" by Daniel F. Galouye.

[Hitmouse]

Galouye is correct. Great book. Have not read it for years. Need to dig it out.

This is about a civilization who went underground following a nuclear war, and who have forgotten about light and the outside world, except as legend.

[hermit]

many thanks Lolrus and Hitmouse, I checked a few sites and I think you are both correct. I really appreciate your help as I have been trying to find this book for a few years now. Already on order :-) I am looking forward to reading it again. Cheers.