DECORUM. or DECOR, in architecture, is the suitableness of a building, and the several parts and ornaments thereof, to the station and occasion. " it consists," says Vitruvius, (book i. chap 2.). " in the proper appearance of a w ork, and its being compounded of approved and authorized parts. This has regard, either to station, which the Greeks call thematismos, custom, or nature. To station, when temples which are erected to -love the Thunderer, the heavens, the stun, or the 'noon, are built uncovered mid exposed to the air, because the influences and effects of those deities are per ceived in the open air ; when to Minerva, Mars, Hercules, Doric temples arc built ; for, on account of the attributes of these deities, edifices constructed without delicacy are most suitable. To Venus, Flora, Prliserpine, and the nymphs of the fountains, the Corinthian kind are erected with propriety ; for by reason of the delicacy of those goddesses, the graceful, gay manner, with foliage and ornamented give a due decorum to the work. To Juno, Diana. Bacchus. and such other deities, Ionic temples are constructed, as holding a posi tion between the two ; for being tempered of the severity of the Pork. and the tenderness of the Corinthian. they become most suitable. Decor, with regard to custom, is observed when the internal parts of edifices being magnificent. the accesses are also made suitable and elegant : for, it' the inte rior parts be elegant, and the approaches mean and ignoble, it will not have decor. So, likewise, it' dentils be carved in
the cornice of the Doric epistylium, or in the abacus of the capital, or if triglyphs be represented in the epistylium of Ionic columns, transferring the characteristics of one kind of work to another ; it ()Maids the eye, because custom has established a different order of things.
Decor, with regard to nature, consists in all temples being placed in a salutary situation, with fountains of water in the places where the fine is built ; but especially the tem ples of YEsculapius, of Health, and such deities, by whose healing influences numbers of sick appear to be recovered. For the diseased bodies being removed from an unhealthy to a healthy situation, and the salutiferous water of the foun tains being administered, they arc soon restored. By this means it will happen, that the natural effects of the place will increase the received opinion of the power of the divinity.
"Decor, with regard to nature, is also observed, when chambers and libraries receive their light from the east ; baths, and winter apartments, from the west ; picture galleries, and such apartments as require as steady light, from the north; because that region of the heavens is rendered neither lighter nor darker by the course of the sun, but is equal and immutable the whole day."