The Collaborative International Dictionary of English v.0.48:

Boule \Boule\, Boulework \Boule"work`\, n.
   Same as Buhl, Buhlwork.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Buhl \Buhl\, Buhlwork \Buhl"work\, n. [From A. Ch. Boule, a
   French carver in wood.]
   Decorative woodwork in which tortoise shell, yellow metal,
   white metal, etc., are inlaid, forming scrolls, cartouches,
   etc. [Written also boule, boulework.]
   [1913 Webster]