Rhett Allain from Wired examines the physics of the dwarves in barrels as they escape down the Forest River. If you like numbers, this will be right up your alley.
Surely you have read The Hobbit (the book). It’s a classic novel and the basis of the upcoming movie The Hobbit: The Desolation of Smaug. The book is old enough that I don’t think I need to give any spoiler warnings. I want to consider the part where the dwarves escape from the elves by floating down a river in barrels.
In the book, Bilbo puts the dwarves in the barrels before they are pushed over into the river. This means that all of the dwarves travel in closed barrels while Bilbo rides on top. Of course some of the dwarves have a comfy trip down the river and some nearly drown. It is up to Bilbo to eventually release the dwarves.
The movie version of The Hobbit has some differences. The movie hasn’t yet been released, but I can guess a few things from the trailer. In the image above, it looks like Thorin is in an open barrel and maybe fighting something or someone. Why? Who knows. Let’s look at the physics involved in floating in a barrel.