  The PHENIX experiment at RHIC has measured transverse energy and charged
particle multiplicity at mid-rapidity in Au + Au collisions at $\sqrt{s_{NN}}$
= 19.6, 130, 62.4 and 200 GeV as a function of centrality. The presented
results are compared to measurements from other RHIC experiments, and
experiments at lower energies. The $\sqrt{s_{NN}}$ dependence of $dE_{T}/d\eta$
and $dN_{ch}/d\eta$ per pair of participants is consistent with logarithmic
scaling for the most central events. The centrality dependence of
$dE_{T}/d\eta$ and $dN_{ch}/d\eta$ is similar at all measured incident
energies. At RHIC energies the ratio of transverse energy per charged particle
was found independent of centrality and growing slowly with $\sqrt{s_{NN}}$. A
survey of comparisons between the data and available theoretical models is also
presented.
