  We present Hubble Space Telescope Imaging Spectrograph (HST/STIS) and Far
Ultraviolet Spectroscopic Explorer (FUSE) observations of high ion interstellar
absorption along the sight line to HD 116852. At a distance of 4.8 kpc, HD
116852 is an O9 III star lying in the low Galactic halo, -1.3 kpc from the
plane of the Galaxy in the direction l = 304.9, b = -16.1. The STIS E140H
grating observations provide high-resolution (FWHM = 2.7 km/s) spectra of the
resonance doublets of Si IV, C IV, and N V. These data are complemented by
medium-resolution (FWHM = 20 km/s) FUSE spectra of O VI. We find evidence for
three distinct types of highly ionized gas present in the data. First, two
narrow absorption components are resolved in the Si IV and C IV profiles, at
approximate LSR velocities of -36 and -10 km/s. These narrow components appear
to be produced in gas associated with the Norma and Sagittarius spiral arms, at
approximate z-distances of -1.0 and -0.5 kpc, respectively. Second, we detect
an intermediate-width component in C IV and Si IV, at 17 km/s, which we propose
could arise at the conductive interface at the boundary between a low column
density neutral or weakly ionized cloud and the surrounding hot medium.
Finally, a broad collisionally ionized component of gas responsible for
producing the smooth N V and O VI profiles is observed; such absorption is also
present to a lesser degree in the profiles of Si IV and C IV. The broad O VI
absorption is observed at a velocity displaced from the broad C IV component by
almost 20 km/s, an amount large enough to suggest that the two ions may not
co-exist in the same physical location.
