EQN and TROFF: Help

[Comp-Phys-P. Gr-19]

I am using eqn, troff, ptroff on a ULTRIX VAX, printing on an Apple
Laserwriter. Now it appears that superscripts like in

.EQ
 {partial sup 2 phi}
.EN

do not print. Is this a problem of eqn or ptroff or am I doing
something wrong? Thanks for any help.

Nick Schaefer, ETH Zuerich
address: gr19 at jungfrau.UUCP
student at technical university of zurich,Switzerland (ETHZ)