Professor Challenger Series Novels

The Disintegration Machine (Professor Challenger 5) by Arthur Conan Doyle
When the World Screamed (Professor Challenger 4) by Arthur Conan Doyle
The Land of Mist (Professor Challenger 3) by Arthur Conan Doyle
The Poison Belt (Professor Challenger 2) by Arthur Conan Doyle
The Lost World (Professor Challenger 1) by Arthur Conan Doyle