  We demonstrate a method for manipulating small ensembles of vortices in
multiply-connected superconducting structures. A micron-size magnetic particle
attached to the tip of a silicon cantilever is used to locally apply magnetic
flux through the superconducting structure. By scanning the tip over the
surface of the device, and by utilizing the dynamical coupling between the
vortices and the cantilever, a high-resolution spatial map of the different
vortex configurations is obtained. Moving the tip to a particular location in
the map stabilizes a distinct multi-vortex configuration. Thus, the scanning of
the tip over a particular trajectory in space permits non-trivial operations to
be performed, such as braiding of individual vortices within a larger vortex
ensemble -- a key capability required by many proposals for topological quantum
computing.
