Abstract: A tube and ball truss system for making a structural lattice which includes a plurality of hollow metal balls spaced in a three-dimensional array, each ball having a set of radial through-openings as well as an access opening on one side, adjacent ones of the balls being interconnected by metal tubes having an outer cylindrical wall and a central axially extending core joined by integral webs, the ends of the core having axially tapped holes engageable by clamping bolts extending through the through-openings in the balls. The ball surface is locally flattened to form land surfaces surrounding the through-openings for flat seating of the end surfaces of the tubes; indeed, the land surfaces are recessed to provide shallow socketed engagement and precise alignment with the ends of the tubes.

Abstract: A building dome structure is formed by splicing long rafter sections into rafters and then lifting the rafters into positions extending meridionally between an upper compression ring and a lower tension ring. Then individual purlins are raised into positions between the adjacent rafters and attached thereto by purlin connecting means. Condensate channels along the rafter and purlin members collect condensation from glazing panels which are supported along their marginal edges by the rafters and purlins.