  We describe measurements demonstrating laser cooling of an atomic gas by
means of collisional redistribution of radiation. The experiment uses rubidium
atoms in the presence of several hundred bar of argon buffer gas pressure.
Frequent collisions in the dense gas transiently shift a far red detuned
optical field into resonance, while spontaneous emission occurs close to the
unperturbed atomic transition frequency. Evidence for the cooling is obtained
both via thermographic imaging and via thermographic deflection spectroscopy.
The cooled gas has a density above 10$^{21}$ atoms/cm$^3$, yielding evidence
for the laser cooling of a macroscopic ensemble of gas atoms.
