Horizontal in situ retorting processes have been developed to recover oil from thin, shallow oil shale deposits. To date the most successful field tests have been conducted in Green River oil shale located in Utah. Consideration is being given to applying this technology to the New Albany oil shales in Indiana. Western Research Institute (WRI) conducted two horizontal in situ oil shale experiments using eastern oil shale and the results are compared with results obtained from a similar experiment using Green River oil shale. The objectives of the three experiments were to simulate the horizontal retorting process and determine oil yield, retorting zone profiles and product characteristics using alternative operating conditions for eastern and western oil shales. The tests proved that horizontal retorting could be simulated in the laboratory. However, air bypass problems occurred in the experiments, which probably reduced oil recovery compared with recovery from field tests. During the eastern oil shale tests plugging was encountered in the gas recovery system because of the production of a solid material containing sulfur compounds. This plugging could be a potential problem for future laboratory and field experimentation. The oil produced from eastern oil shale has different properties from western shale oil. The oil is highly aromatic and when hydrogenated may yield a prototype high density jet fuel. 10 refs., 8 figs., 11 tabs.