In any rapid pyrolysis solid-recycle retorting system the degree of solid mixing necessary to accomplish full conversion of kerogen to oil is an important consideration. Using the Livermore pilot retort the extent of solid mixing was varied and the effect was observed on solid temperatures and kerogen conversion within the gravity bed retort. The results of this investigation are described. Water formation during oil shale pyrolysis has an impact on both chemistry and energy balance in a retort. A mass spectrometry method was developed and applied to the study of water evolution from batch pyrolysis of oil shale. Results of this study are also described in this report. 6 figs., 1 tab.