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Using archival data of low-redshift (z < 0.01; CfA and SUSPECT
databases) Type Ia supernovae (SN Ia) and recent observations of
high-redshift (0.16 < z <0.64; Matheson et al. 2005) SN Ia, we study
the ``uniformity'' of the spectroscopic properties of nearby and
distant SN Ia. We find no difference in the measures we describe
here. In this paper, we base our analysis solely on line-profile
morphology, focusing on measurements of the velocity location of
maximum absorption (v_abs) and peak emission (v_peak). We find that
the evolution of v_abs and v_peak for our sample lines (Ca II 3945,
Si II 6355, and S II 5454, 5640) is similar for both the low- and
high-redshift samples. We report for the first time the unambiguous
and systematic intrinsic blueshift of peak emission of optical P-Cygni
line profiles in Type Ia spectra, by as much as 8000 km/s. All the
high-z SN Ia analyzed in this talk were discovered and followed up by
the ESSENCE collaboration, and are now publicly available.
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