  The rational homology balls $B_n$ appeared in Fintushel and Stern's rational
blow-down construction [FS] and were subsequently used (e.g.
Fintushel-Stern[FS4], Park[Pa2]) to construct exotic smooth manifolds with
small Euler numbers. We show that a large class of smooth 4-manifolds have all
of the $B_n$'s for odd $n \geq 3$ embedded in them. In particular, we give
explicit examples, using Kirby calculus, of several families of smooth
embeddings of the rational homology balls $B_n$.
