Seneca scaffolds the text of Naturales Quaestiones 3 to mimic the physics of the subject of the book: terrestrial waters. As waters below the earth correspond to those above, so Seneca utilizes specific textual references. Quotations, like visible waters, can be recognized and understood by all. Seneca, however, encourages his reader to move beyond the surface to the intertextual substrata through his advice in the preface and the various signposts to such allusive material in this opening book. Intertexts to Vergil and Ovid (among others) act like underground waters to be understood through the employment of ratio and careful study.