Adsorption studies carried out on ancient Egyptian mortars suggest that these materials are essentially nonporous with a certain degree of mesoporosity. The adsorption data were analyzed by using 2 reference nonporous materials. Surface activity was observed as a result of heat treatment. Infrared studies confirmed that the samples contained gypsum, calcite, and quartz sand with a clear-cut predominance of gypsum in the mortars extracted from the Sphinx statue. A correlation is perceived between these results and the x-ray diffraction results obtained in Part I of this series. -- AATA