  Lithium is one of the few primordially produced elements. The value of the
primordial Li is taken to be that observed in metal--poor dwarfs, where it is
not contaminated by stellar Li sources which act on longer time scales. The
atmospheric abundance is currently derived from the LiI 6707 Angstroem
resonance transition and the validity of the models employed has been
questioned (Kurucz 1995). In this letter we report the first detection of the
Li I 6104 Angstroem 2^2P - 3^2D subordinate transition in the prototype
population II star HD 140283. The same Li abundance of (Li/H) =1.4x10^{-10} is
found consistent with both the resonance and subordinate lines. The two lines
form at different depths in the atmosphere implying that the 1-D homogeneous
atmospheric models used in the abundance determination are essentially correct.
When coupled with the standard big bang yields, the Li in the halo dwarfs
provides two solutions for the baryon-to-photon ratio \eta_{10}=
n_{b}/n_{\gamma} x 10^{10}and for the present baryon density \Omega_b
h_{70}^2=0.0748\eta_{10}: a) a first solution at \eta_{10} about 1.8,
consistent with the \eta_{10} implied by the high deuterium values D/H\approx 2
x 10^{-4}observed in some quasar absorption systems (Webb et al 1997) and b) a
second solution at \eta_{10} about 4 which is consistent, within the errors,
with the low deuterium D/H =3.4x10^{-5} measured in other quasar absorption
systems (Burles & Tytler 1998).
