they all warily disembarked , and unloaded the dragons ; then temeraire reared up on his hind legs and set his claws into the side of the rising dune and pulled it down , cascading sand and the narrow trees sliding askew , to bury all the dark gaping mouths : the tunnels vanished beneath the spill of darker red earth , and they all beat down upon it with the backs of shovels , to trample it flat and smooth , and then without any orders , the men began to roll over whatever rocks of any size they could find , and the toppled trunks , to make an entrenched border around the site .