Parthenon: section of Posticum, looking east. section of Posticum taken through the centre of the temple, toolane south. Plate 16, Chapter VI. By Francis Penrose, 1888.
An investigation of the principles of Athenian architecture: or the results of a recent survey conducted chiefly with reference to the optical refinements exhibited in the construction of the ancient buildings at Athens.
Francis Penrose, 1888
Source: https://digi.ub.uni-heidelberg.de/diglit/penrose1888
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