“Roll out the barrel, we'll have a barrel of fun.
Roll out the barrel, we've got the blues on the run.
Zing boom tararrel, ring out a song of good cheer.
Now's the time to roll the barrel, for the gang's all here.”

(Melody:  Jaromir Vejvoda; English lyrics:  Lew Brown, Vladimir Timm—perhaps the first famous US performance was by the Andrews Sisters 
in 1939—here’s a recording:  https://www.youtube.com/watch?v=7KRc-ceWE2E )
As ever, welcome, dear readers.

This is the 400th posting of doubtfulsea.com and perhaps a small rolling out of barrels is due, but “barrels” has immediately made me think of another kind of barrel rolling—
and, as always, I wonder about sources:  where might the idea of escape by barrel have come from?
It seems certain that Tolkien had had read to him or had read to himself Andrew Lang’s Red Fairy Book (1890),
which has in it “Storia Moria Castle” and the dragon which was probably the one which sparked his imagination as he recounted in his long, rich letter to W. H. Auden of 7 June, 1955 (see Letters, 214).  Had he also encountered the first book in Lang’s long series of colored fairy books,
 the Blue Fairy Book (1889),
he would have heard the story “The Forty Thieves”, probably known to you as to me as “Ali Baba and the Forty Thieves”.
 If you’re unfamiliar with this story, in brief (very brief—the story is a bit more complicated than this) it goes like this:
1. Ali Baba works as a wood cutter for a living.
2. one day, he hears horsemen approaching where he’s working and he climbs into a tree to watch.
3. they approach and he watches one, seemingly the chief, dismount, step to a cliff face, and murmur “Open Sesame!”
4. a door opens and the chief goes inside, followed by his other—39—Ali Baba counts them—men.
And yes, this does have the echo of something else, doesn’t it?  (See The Fellowship of the Ring, Book Two, Chapter 4, “A Journey in the Dark”)  Perhaps this might be evidence that JRRT did know Lang’s volume?
5. after the 40 leave, Ali Baba slips down, tries the password, and finds himself in a cave stuffed with riches.
6. loading up his mules with treasure, he takes home a selection of what he found in the cave.
7.  in time, the chief realizes that the cave has been looted and that Ali Baba did it and, disguised as an oil merchant, he gains access to Ali Baba’s house, his men concealed in a cargo of oil jars.
 8. unfortunately for his men, Ali Baba has a clever slave named Morgiana, who discovers what’s in the jars and fills them with burning oil, thereby removing the chief’s band.
And so we see that those jars might someday turn into barrels.
(an Alan Lee illustration)
As I’ve written before, Tolkien began his academic life intending to become a Classicist, and so another rather unusual escape story might also have been in the back of his mind.
Odysseus and his men are in terrible trouble, trapped in a cave with a one-eyed giant, a Cyclops, who, over about two days, has eaten six of those men.
They can’t kill him and escape because the Cyclops seals the door with an enormous boulder, which only he can push out of the way.  In a flash of the genius which makes him “polymetis”, “manyplans”, as he’s called in the Odyssey, Odysseus gets the Cyclops drunk, and, when he collapses in a stupor, blinds him.
The Cyclops is a herder of sheep and goats and, in the morning, he is due to let them out out of his cave so that they can proceed to graze.  Odysseus realizes this and binds his men under six of the biggest sheep (figuring that, if the Cyclops searches for escaping men, he’ll pass his hands across the sheeps’ backs), then clings to the underside of a big ram and follows them out (after a hairy moment when the Cyclops stops the ram—his favorite, it turns out—and has a brief chat with it). 
Although using neither pots nor barrels, might we see a familiar pattern here, rescuer sending the rescued ahead, then, clinging to something, tagging behind? 
Thanks, for reading, as ever, and
Stay well,
Have an escape route,
And remember that there’s always
Here’s your copy of the first edition of the Blue Fairy Book: https://archive.org/details/bluefairybook00langiala/mode/2up  “The Forty Thieves” is on pages 242-250. 

My apologies for the weird typeface and the spacing.  As I move on to #401, I assure you that I'm not making a change!  I have no idea what's happened--perhaps it's that mention of the Andrews sisters?  Certainly, this type makes the posting look like it dates from 1939.