I believe the Bible and it isn’t in conflict with the coracles theory. It was likely lozenge-shaped.
See here: http://www.freerepublic.com/focus/news/3115493/posts?page=25#25
Lol. Make up your mind. That is not "round." That is a rectangle with rounded corners.
I guess the Tent of Meeting was also shaped like this?
What about the Ark of the Covenant? The Holy of Holies? The Temple itself?
All of these have specific dimensions defined in scripture. Width and Height by definition do not define something "round" as described in the article above.