  We describe the construction of a prototype hybrid permanent magnet dipole
and quadruple. The magnet consists of two concentric rings of SmCo magnetic
material 5 cm in length. The outer ring is made of 16 uniformly magnetized
blocks assembled as a Halbach dipole and the inner ring has 32 blocks oriented
in a similar fashion so as to generate a quadruple field. The resultant
superimposed field is an offset quadruple field which allows us to center the
field on the high-energy beam in the interaction region of the PEPII B factory.
The dipole blocks are glued to the inside surface of an outer support collar
and the quadruple blocks are held in a fixture that allows radial adjustment of
the blocks prior to potting the entire assembly with epoxy. An extensive
computer model of the magnet has been made and from this model we developed a
tuning algorithm that allowed us to greatly reduce the n=3-17 harmonics of the
magnet.
