  Using the PQSCHA semiclassical method, we evaluate thermodynamic quantities
of one-dimensional Heisenberg ferro- and antiferromagnets. Since the PQSCHA
reduces their evaluation to classical-like calculations, we take advantage of
Fisher's exact solution to get all results in an almost fully analytical way.
Explicitly considered here are the specific heat, the correlations length and
susceptibility. Good agreement with Monte Carlo simulations is found for S>1
antiferromagnets, showing that the relevance of the topological terms and of
the Haldane gap is significant only for the lowest spin values and
temperatures.
