 thumb|temple of jupiter olympus, painting henry byam martin (1835) showing hypaethral opening hypaethros or hypaethral opening is the greek term quoted by vitruvius (iii. 2) for the opening in the middle of the roof of decastyle temples, an example being found in athens in the temple of jupiter olympius, which is octastyle. there was no example in rome. however, at the time vitruvius wrote (c. 25 ad) the cella of this temple was unroofed, because the columns which had been provided to carry, at all events, part of the ceiling and roof had been taken away by sulla in 80 bc. the decastyle temple of apollo didymaeus near miletus was, according to strabo (c. 50 bc), unroofed, on account of the vastness of its cella, in which precious groves of laurel bushes were planted. thumb|temple of aphaea in aegina apart from these two examples, the references in various writers to an opening of some kind in the roofs of temples dedicated to particular deities, and the statement of vitruvius, which was doubtless based on the writings of greek authors, that in decastyle or large temples the centre was open to the sky and without a roof (medium autem sub diva est sine tecto), render the existence of the hypaethros probable in some cases; and therefore c. r. cockerell's discovery in the temple at aegina of two fragments of a coping-stone, in which there were sinkings on one side to receive the tiles and covering tiles, has been of great importance in the discussion of this subject. in the conjectural restoration of the opaion or opening in the roof shown in cockerell's drawing, it has been made needlessly large, having an area of about one quarter of the superficial area of the cella between the columns, and since in the pantheon at rome the relative proportions of the central opening in the dome and the area of the rotunda are 1:22, and the light there is ample, in the clearer atmosphere of greece it might have been less. the larger the opening, the more conspicuous would be the notch in the roof which is so greatly objected to; in this respect, jacques hittorf would seem to be nearer the truth when, in his conjectural restoration of temple r at selinus, he shows an opaion about half the relative size shown in cockerell's of that at aegina, the coping on the side elevation being much less noticeable. the problem was apparently solved in another way at bassae, where, in the excavations of the temple of apollo by cockerell and baron hailer von hallerstein, three marble tiles were found with pierced openings in them about 18 inches by 10 in.; five of these pierced tiles on either side would have amply lighted the interior of
Ancient_Greek_architecture Ancient_Roman_architecture