De parietibus et apparitione generatim materiae eorum, quibus sint virtutibus et vitiis, quemadmodum potui, exposui; de contignationibus autem et copiis earum, quibus conparentur, et ad vetustatem non sint infirmae, uti natura rerum monstrat, explicabo.
With respect to walls and the use of material after its kinds, I have explained their excellences and faults as I have been able. Now with respect to floors and the material from which they are provided, so that they may not be weakened by lapse of time, I will explain as nature shows.
final_alignments\Vitruvius_Architecture_Book_2.json