  We re-examine the ordering behavior of a one-dimensional fluid of freely
rotating hard needles, where the centers of mass of the particles are
restricted to a line. Analytical equations are obtained for the equation of
state, order parameter and orientational correlation functions using the
transfer-matrix method if some simplifying assumptions are applied for either
the orientational freedom or the contact distance between two needles. The
two-state Zwanzig model accounts for the orientational ordering, but it
produces unphysical pressure at high densities and there is no orientational
correlation. The four-state Zwanzig model gives reasonable results for
orientational correlation function, but the pressure is still poorly
represented at high densities. In the continuum limit, apart from the
orientational correlation length it is managed to reproduce all relevant bulk
properties of the hard needles using an approximate formula for the contact
distance. The results show that the orientational correlation length diverges
at zero and infinite pressures. The high density behavior of needles is not
resolved.
