TURKISH ESSENCE.

A clear, precise statement, the Turkish pavilion attempts the essence of a nationality.

Turkey's pavilion is a building in a cage. A rectangular steel structured box, some 12m high, clad in aluminium and glass, is wrapped to south, east and west by timber screens. With their 300mm square grillages, the screens, made of treated pine, are clearly an abstraction of the Middle Eastern mashrabiya, the traditional wooden screen that protects windows from the sun and from intrusive glances, while allowing air to circulate and inhabitants to look out.

Between screens and building are long thin pools, symbolic of the three seas that surround Anatolia. On the south side, a gently arcing timber bridge hovers over the water and gently delivers visitors to the entrance, three metres above ground. Inside, you find yourself on the middle of three square platforms made of the same timber as the screens. In front is a long glass reception desk with, when I was there, a mass of beautiful scarlet species tulips (Turkey's national flower) in glass troughs underneath (what happens when the tulips are over?). To the left is the highest platform, with a glittering silver plexiglass globe in its centre; to the right is the lower one.

Reaching the ground between the olives, you can study the videos of the country, or turn round to be reminded of the traditional cantilevers of old Turkish timber houses in the structure of the platforms, which bear out from massive trabeated frames of laminated timber, with their construction clearly articulated. On the ground beneath the platforms is the shop and more gallery space. From this level, you can rise again by a grand stair (or lift -- for once, movement for the handicapped is not difficult) to a gallery which runs all along the north side of the exhibition space. This is enclosed in a rectangular box which runs parallel to the main one and projects slightly to the west. At ground level, this volume contains services, offices and so on. Its gallery level is full of light, and decorated with modern versions of Iznik tiles, the wonderful blues of which traditionally celebrated fine public buildings. At this level is a 16m long table formed like a boat where 50 can sit down together at what the org anizers call a traditional Turkish communal table. (It's a genial idea, but I've never come across a real one in Turkey.) Externally, this back block is not the most successful part of the building: the layered transparency of the front changes abruptly to opaque panels part of the way along the north elevation, and the window openings do not coincide with the square grid of the panels.

But much can be forgiven for the internal space, the layered treatment of front and sides -- and for the environmental control system. On hot days the greenhouse effect of a big glass building is combated not only by the mashrabiyas, but also by convection. Air is drawn in over the cooling water through louvres in the glass wall, then rises to be expelled through the plexiglass pyramids in the roof and through the northern clerestory at the vertical junction between the two plan elements. Such automated convected climatic control is by no means unusual these days, but in the Turkish pavilion it is more clearly articulated than in any other at Expo.