the figures without such planes on which to stand. Thus this vision of heavenly space becomes a weak version of the more solidly realized space in the earthly section of the painting, rather than the unique type of space for which Botticini seems to be aiming. Tura, on the other hand, makes his space magical or supernatural by simply ignoring what might be to the sides or in front of the scene he shows (the 'sides' of Botticini's vision are what make it so unconvincing) and then, very subtly, suggesting unlimited open space behind his altar-like architecture.
1 d Tura attempts to establish an overall pattern that is very tightly organized and carefully balanced. In his painting, colour is one of the balancing elements. In this sense it is an intrinsic part of the composition. The alternating bright pinks and greens mark this as another world, and contribute heavily to the patterned effect. These colours alternate as regularly as the directions of the figures' heads, or the shapes of the instruments. In the two figures who kneel at the fountain, the greens and browns of their robes are reversed in a similar fashion. For Botticini, patterning is less important and the use of colour is less schematic. The colours of the figures in heaven are carefully selected to avoid monotony, but those of the figures of the Apostles and of the Palmieris are much more subtly balanced. The glow of the earthly landscape also contrasts with the glare of the heavenly scene, and this gives a different value (and meaning) to the colors in the two parts of the painting.
1 e Both paintings try to deal with the problem of representing a heavenly subject in terms of earthly (or human) appearances. This is the same goal as the paintings by the two Lippis. This combination of the earthly and the heavenly was clearly an important problem addressed by painters of the fifteenth century. Paintings for churches had to present sacred subjects in a ma...