  Recently Murayama & Taniguchi proposed that a significant part of the
high-ionization nuclear emission-line region (HINER) in Seyfert nuclei arises
from the inner wall of dusty tori because type 1 Seyfert nuclei (S1s) show the
excess HINER emission with respect to type 2 Seyfert ones (S2s). This means
that the radiation from the HINER has the anisotropic property and thus
statistical properties of the HINER emission can be used to investigate the
viewing angle toward dusty tori for various types of Seyfert nuclei. In order
to investigate viewing angles toward various types of Seyferys, we apply this
HINER test to them.
  Our main results are as follows. (1) The NLS1s are viewed from a more face-on
view toward dusty tori than the S2s. However, the HINER properties of the NLS1s
are indistinguishable from those of the S1s. (2) The type 1.5 Seyferts appear
to comprise heterogeneous populations. (3) The type 1.8 and 1.9 Seyferts and
the objects showing either a broad Pa_beta line or polarized broad Balmer lines
are seen from a large inclination angle and the emission from the BLRs of such
objects reaches us through optically-thin parts of dusty tori. These three
results support strongly the current unified model of Seyfert nuclei. And, (4)
the line ratios of [Fe X]6374 to the low-ionization emission-lines have rather
isotropic property than those of [Fe VII]6087. Therefore it is suggested that
the [Fe X] emission is not useful investigating the viewing angle toward the
dusty torus in Seyfert nuclei. The most plausible reason seems that the [Fe X]
emission is spatially extended and thus its strength tends to show less viewing
angle dependence.
