Apparently the Turks had been in too much of a hurry to trundle siege artillery all the way across Hungary and so they were undoing the work of the Engineers one shovel-load at a time. Vienna's walls and bastions had been smooth regular shapes, so the Turks' handiwork was as obvious as a mole-hill in a Duke's bowling-green. They had dug a metropolis of trenches in what had been a perfectly flat glacis. Each trench was surrounded by the dirt that had been flung out of it, giving it the swollen look of an infected wound. A few of these trenches led straight from the heart of the Turkish camp toward the Emperor's Palace, but these were just the great avenue-trenches from which countless street-trenches branched off left and right, running generally parallel to the city's walls, and spaced as closely together as they could be without collapsing. These trenches were as rungs in a horizontal ladder by which the Turks had advanced until they'd reached the foot of the first ravelins: outlying, arrowhead-shaped earthworks between bastions. Here they had gone underground and undermined the ravelins, packed the mines with black powder, and blown them up, creating avalanches where walls had stood – as when molten wax spills from the top of a candle and mars its regular shape with a lumpy cataract. Fresh trenches, then, had been cut across those irregular debris-piles, bringing the Turks into a position whence they could bring musketry to bear on the city walls, to protect their sappers and miners as they advanced, ditch by ditch, across the dry moat. Now they were attacking the great bastion directly before the Palace in the same way. But it was a gradual sort of war, like watching a tree absorb a stone fence, and nothing was happening at the moment.