Another part of the research on the houses of medium standing regarded the architectural types widespread in Pompeii between the end of IV and the beginning of I c. B.C. Unlike the study of Casa del Granduca Michele, mainly based on excavations data, this research had to deal with the bad conservation of the structures dating to this period and with the subsequent difficulty of reconstructing this phase of the analysed buildings. The reconstruction of the rear of these houses has been particularly difficult, because it has often been interested, by the end of II c., by transformations that are scarcely retraceable without excavations. In absence of archaeological reports, this difficulty implicated the choice to concentrate the studying of architectural structure of houses of medium standing on the foreword sector, occupied by the atrium. The latter, in fact, has been concerned, during the centuries, by a small number of transformations that kept the layout almost unchanged. Therefore, this study has concerned mainly the different types of atrium employed to build the houses of medium standing, highlighting their features and diffusion. Firstly, the atrium compluviatum types have been analysed, i.e. the Tuscan, the Corinthium and the Tetrastyle atrium. Their diffusion and use in the houses of medium standing have been studied. These types of atrium were employed firstly in the elite dwellings and then in the houses of medium standing, where the little size of plots compelled to adjust the original model by the abolition of some of the rooms bordering the atrium, particularly of those on the long sides. A particular attention has been paid to the study of atrium testudinatum houses, the analysis of which had been neglected before, in favour of the forms of atrium with compluviatum ceiling. The latter represents, in fact, the more widespread architectural typology for the construction of upper standing houses, attracting the attention of researchers more than the types used in medium standing houses. On the contrary, the testudinatum type, being employed mainly for the building of humbler houses, was, with some exception, largely ignored. The research regarding this architectural type has been carried out by an in depth survey that allowed the finding of about sixty atrium testudinatum houses, dating back to the period comprised between the end of IV and the mid II c. B.C. These houses are analysed in a catalogue attached to chapter II, that does not include all the atrium testudinatum houses of Pompeii for this period, but a sample of them, which is large and highly representative. The houses analysed in the catalogue are characterized by atria varying a lot in form and size, pertaining to dwellings built in different moments and in different parts of the town. This variety has offered interesting data about the diachronic and topographic diffusion of this type of house, and about its architectural features. Finally, in chapter II, an analysis of bathing rooms has been done. The existence of this kind of room in the houses of medium standing for this period had not been highlighted yet. It has been noticed only recently thanks to the discovery of Protocasa del Granduca Michele above all. The bathing rooms have been studied in the houses of medium standing of Pompeii and in other Hellenistic sites around the Mediterranean Sea.
