Petra- “Treasury”

  • I started with the axes of the outer columns. I will call the distance from those axes to the centerline 1 unit, so that the width between those axes is 2 units. The height of the column shafts in the first story is 1 unit, so that this area forms a double square (slightly smaller than the one that you found around the exterior of the composition; more on that below…)

    I stepped in by quadrature, and found the width of the door opening, which is (root2)/4, or .354, in addition to noticing that the right-hand column flanking the door sits further outboard than its pendant to the left.

Petra Deir- “Monastery”

  • Begin with a square, aligned with the axes of the main temple front, and call its side length 1.000. Set its equator even with the baseline of the main lower entablature, i.e. with the top edges of the lower capitals at height .500. Its top edge will align closely with the top edge of the natural wall behind, seen at left. Draw a circle around the square, noting that its top point at height 1.207 locates the baseline of the second story entablature.