  In this paper we describe the electrons of the 1D Hubbard model by a fluid of
unpaired rotated electrons and a fluid of zero-spin rotated-electron pairs. The
rotated electrons are related to the original electrons by a mere unitary
transformation. For all finite values of energy and for the whole parameter
space of the model this two-fluid picture leads to a description of the energy
eigenstates in terms of occupancy configurations of $\eta$-spin 1/2 holons,
spin 1/2 spinons, and $c$ pseudoparticles only. The electronic degrees of
freedom couple to external charge (and spin) probes through the holons and $c$
pseudoparticles (and spinons). Our results refer to very large values of the
number of lattice sites $N_a$. The holon (and spinon) charge (and spin
transport is made by $2\nu$-holon (and $2\nu$-spinon) composite pseudoparticles
such that $\nu=1,2,...$.
