Iota Orionis is a massive binary with a very eccentric orbit, which br
ings the stars into close proximity at periastron. The resulting tidal
deformation of the primary star is expected to create enhanced mass l
oss and stimulate stellar oscillations at each periastron. We present
the results of a search for these effects in high S/N spectra of the H
alpha and He I lambda 6678 profiles of I Ori obtained over 5.5 hr dur
ing a single periastron passage. We fit the He I lambda 6678 data usin
g previously determined profiles for both components and using the orb
ital solution of Stickland et al. (1987) to establish that periastron
occurred at HJD 2,450,072.80 +/- 0.03. Measurements of the projected r
otational velocities indicate that both stars rotate more slowly than
the orbit at periastron. There is weak, residual H alpha emission that
moves with the primary's orbital motion and that may be associated wi
th the development of an enhanced, focused wind at periastron. However
, the He I lambda 6678 line of the primary star is nearly constant in
shape over this interval and we find no evidence for tidally induced o
scillations.