The Complete Professor Challenger Stories (Sir Arthur Conan Doyle)

I'm a big fan of The Lost World - recently re-read it because of connection to a book club selection.

Hadn't previously seen other Professor Challenger stories.  This volume was a birthday gift from Charlie . . . who had received it from Carol.

The Poison Belt - the earth passes through an area of space that threatens to wipe out human life.

The Land of Mist - this is just pretty weird - ACD was into the occult stuff (as was the case for many of his era).

The Disintegration Machine - short, just what it sounds like, the inventor is trying to sell it to a hostile foreign power.

When the World Screamed - Challenger leads a deep dig.

Generally the same characters as in The Lost World.  Bickering with Summerlee.  Lord John Roxton.  Malone.