George Wetherill stepped down as Director on 30 June 1991, having attained the mandatory age of 65 for retirement from an administrative position, although he remained as a member of the scientific staff. He could look with satisfaction on the Department's scientific condition. The three categories of seismology, geochemistry and astronomy were independently strong and had healthy intellectual contacts with one another and the international scientific world. The two geologically oriented sections both sought to understand the functioning of the Earth and its most ancient history. Astronomy had a sufficiently strong component of star and planet formation to provide a healthy exchange of ideas, as enlivened discussions at seminars demonstrated, and the geochemists' concentration on terrestrial rocks resulted from the rarity of significantly different extraterrestrial samples, not the narrowness of their interests.

He had found his relations with the President less satisfying. He had left the Institution during Tuve's tenure when outside funding was rarely encountered and was never used to support routine Department research activities. This strict rule had been breached during the Bolton years, and on returning to the Institution to become Director, Wetherill had continued to allow individual investigators to accept grants. This form of financing was given strong emphasis when James Ebert became President, as he insisted that investigators submitting proposals apply not only for their immediate research needs, such as equipment, laboratory and field expenses, and support for visiting scientists, but also for part of their salaries and for substantial amounts of overhead.