Tectum porticus, quod futurum est in summa gradatione cum scaenae altitudine libratum perspiciatur, ideo quod vox crescens aequaliter ad summas gradationes et tectum perveniet.
The roof of the colonnade, which is to be built on the top row of steps, is to be so planned as to be level with the top of the back wall of the stage, because thereby the voice will rise evenly until it reaches the top seats and the roof.
final_alignments\Vitruvius_Architecture_Book_5.json