Eaque columna versatilis perficiatur, uti ad sigillum virgulamque, qua virgula egrediens sigillum ostendit horas, columna versando continenter suis cuiusque mensibus brevitates et crescentias faceret horarum.
The lines of the months also are to be marked on the column. And this is to be made to revolve uninterruptedly, so that it turns to the figure and the rod (with which rod the figure as it moves on shows the hours), and so causes the shortening and lengthening of the hours, in their several months.
final_alignments\Vitruvius_Architecture_Book_9.json