  Experimental results and a detailed analysis are presented of the transverse
energy and charged particle azimuthal distributions measured by the E877
collaboration for different centralities of Au+Au collisions at a beam momentum
of 10.8 A GeV/c. The anisotropy of these distributions is studied with respect
to the reaction plane reconstructed on an event-by-event basis using the
transverse energy distribution measured by calorimeters. Results are corrected
for the reaction plane resolution. For semicentral events we observe directed
flow signals of up to ten percent. We observe a stronger anisotropy for slow
charged particles. For both the charged particle and transverse energy
distributions we observe a small but non zero elliptic anisotropy with the
major axis pointing into the reaction plane. Combining the information on
transverse energy and charged particle flow we obtain information on the flow
of nucleons and pions. The data are compared to event generators and the need
to introduce a mean field or nucleon-nucleon potential is discussed.
