  A result from Dodd and Gibbs[1] for the second virial coefficient of
particles in 1 dimension, subject to delta-function interactions, has been
obtained by direct integration of the wave functions. It is shown that this
result can be obtained from a phase shift formalism, if one includes the
contribution of oscillating terms. The result is important in work to follow,
for the third virial coefficient, for which a similar formalism is being
developed. We examine a number of fine points in the quantum mechanical
formalisms.
