I recently came across an interesting short article on the acoustics of violin bodies. From Benning Violins, California:
The body of violins, including their front and back plates, their sides as well as the air they contain, all function as part of the process of transmitting the string vibrations through the bridge into the air surrounding the instrument. The surface area of the violin is in direct relation with the amount of air it vibrates back and forth.
Now that you're interested, the rest of this interesting article is located at the source for the above text: http://www.benningviolins.com/the-acoustics-of-the-violin-body.html