In the annunciation of the death of the virgin (13.23), duccio employs an innovative use of

In the annunciation of the death of the virgin 13.23, duccio employs an innovative use of architecture. During this period the most fervent development in painting occurred in Italy. At the end of the thirteenth century, Italian artist began demonstrating an astonishing genius for strikingly dramatic works. Incorporating the neo greek influences acquired from the fourth crusade with the gothic style and a bold new emotional intensity was exposed. The first major step eliminating painting from the architectural setting of other art forms can be seen in the Annunciation of the Death of the Virgin by the Sienese master, Duccio. Earlier painters always placed architectural features in arrears the figures which makes a new perspective of space and depth. While duccio, in structural space and depth on a two dimensional surface, opening a window onto a distant scene, giotto distilled these concepts of depth and space to startling simplicity drawing the viewer into a picture. 

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convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.