Mr Segundus found two stone dragons no longer than his forearm, which slipped one after the other, over and under and between stone hawthorn branches, stone hawthorn leaves, stone hawthorn roots and stone hawthorn tendrils. They moved, it seemed, with as much ease as any other creature and yet the sound of so many stone muscles moving together under a stone skin, that scraped stone ribs, that clashed against a heart made of stone - and the sound of stone claws rattling over stone branches - was quite intolerable and Mr Segundus wondered that they could bear it. He observed a little cloud of gritty dust, such as attends the work of a stonecutter, that surrounded them and rose up in the air; and he believed that if the spell allowed them to remain in motion for any length of time they would wear themselves away to a sliver of limestone.