  The elastic and capillary interactions between a pair of colloidal particles
trapped on top of a nematic film are studied theoretically for large
separations $d$. The elastic interaction is repulsive and of quadrupolar type,
varying as $d^{-5}$. For macroscopically thick films, the capillary interaction
is likewise repulsive and proportional to $d^{-5}$ as a consequence of
mechanical isolation of the system comprised of the colloids and the interface.
A finite film thickness introduces a nonvanishing force on the system (exerted
by the substrate supporting the film) leading to logarithmically varying
capillary attractions. However, their strength turns out to be too small to be
of importance for the recently observed pattern formation of colloidal droplets
on nematic films.
