Is this “18” hours (as in lesson II) or “18 and a half” hours as in lesson III? (I believe it’s the former, but want to know if I’m maybe missing something.)
Salve:)
18 (6pm)
Septimum decimum= 17
Duodevicesimum=18
Undevicesimum=19
Vicesimum=20
…
Duodetricesimum=28
Undetricesimum=29
et cetera:)