The card known as Temperance or as Art in the Thoth deck and in my Tabula Mundi Tarot, is called The Arc in my new deck Pharos Tarot. The title refers both to the Arc of the rainbow, the Ark of the covenant, and to something called “the Arc of Visibility”. That’s a nautical term that refers to the portion of the horizon over which a lighted aid to navigation (ie a lighthouse or a star) is visible from seaward.
The Hebrew letter Samekh means “prop”. The Arc is upheld by a skull shaped prop showing that the Death card is the foundational stage preceding it.