  We report on the detection of a strong, organized magnetic field in the
helium-variable early B-type star HR 7355 using spectropolarimetric data
obtained with ESPaDOnS on CFHT by the MiMeS large program. We also present
results from new V-band differential photometry obtained with the CTIO 0.9m
telescope. We investigate the longitudinal field, using a technique called
Least-Squares Deconvolution (LSD), and the rotational period of HR 7355. These
new observations strongly support the proposal that HR 7355 harbors a
structured magnetosphere similar to that in the prototypical helium-strong
star, sigma Ori E.
