Abstract: A study has been made of the source, acceleration, and neutralization of ions for application to space propulsion. A summary is made in this paper of some of the most important problems in this area and their solutions.

In a recent paper, Bowers and Salpeter described a method for calculating the correlation energy of a classical one-component electron gas. The same problem has been considered by Meeron, Friedman, and Abe, using methods involving the summation of cert infinite classes of diagrams. While the relation between these theories and that of Bowers and Saltpeter is not year clear, it is interesting to note that Abe obtained an equivalent expression by approximating an integral. We have calculated the contribution to the equation of state using Abe's original expression and we found that the equation is valid only for certain values and it gives a correction of the wrong sign. On the other hand, our results are comparable to those which Bowers and Salpeter obtain from higher approximations.