The Lost World by Arthur Conan Doyle (John Murray, 1960)

If you take the trouble of searching the dusty shed part of The Green Shed you can find some amazing stuff:

 

On a high plateau in South America a group of explorer-scientists led by the famous Professor Challenger discovered a huge tropical marsh surviving from prehistoric times inhabited by giant reptiles and the grotesque half-ape forerunners of man.  In the face of fantastic dangers they capture one of the flying reptiles and bring it back to London, where it escapes and causes havoc.  The Lost World was the first of the full-length novels of this kind, and its breathtaking combination of science and fiction and real characters keeps it without a rival.

Everyone knows Arthur Conan Doyle as the creator of Sherlock Holmes.  Less well known are his ventures into writing science fiction and fantasy.  The Lost World (1912) is the first in a series of three novels featuring the bullish and eccentric Professor Challenger: the others being The Poison Belt (1913) an end-of-the-world story, and The Land of Mist (1926) a rather too-credulous look at the claims of spiritualism.

This first novel is literally a "lost world" story, with Professor Challenger and his band of intrepid explorers finding an isolated plateau  in South America inhabited by dinosaurs.  Evidently South America was to the average person of 1912 as outer space is today--a place where anything could happen, and strange things  could be found!