Our good friend Ariadne mentioned that she was reading Mysterious Island by Jules Verne. The Mysterious Island follows the adventures of a group of castaways who use their survivalist savvy to build a functional community on an uncharted island. A hot-air balloon carrying five passengers and a dog
escapes from Richmond, Va., during the American Civil War. It is blown
off course and deposited near an obscure island. One of the castaways
nearly dies after a skirmish with pirates; he is saved by the
unexplained appearance of medicine after the pirates are unexpectedly
routed. The group later discovers that their secret helper is the
reclusive Captain Nemo (first introduced in Verne's Twenty Thousand
Leagues Under the Sea), who dies and is buried at sea in his submarine.
The castaways are eventually saved by a passing ship.

• You can read it online here.
• For your Kindle.
• Project Gutenburg - Works for Apple products and others.