Hubble’s Constant is an experimental relationship between the speeds and separations of galaxies.  It is shown that this information can be combined with the results of differential calculus to obtain an estimate of the value of the outward acceleration of each galaxy.  On this basis, it is found that the speed of each galaxy increases with time while the corresponding separations from Earth vary as the square of this quantity.  This relationship in turn indicates that the value of Hubble’s Constant increases linearly with time, which means that it serves as a clock of the universe.  These results are seen to be consistent with the “expanding universe” cosmological theory, but stand in contradiction to Einstein’s supposition that the curvature of space is sufficient to ultimately allow for a slowing down of the expansion and even reverse it if there is sufficient mass for this to occur.  Finally, it is shown that when the Laws of Thermodynamics are applied backward in time that the expectation is that state of matter is reached in which the value of the entropy of the universe is zero.