the exhausted dragons slept eight hours , in four watches , with the french dragons always under a wary eye ; laurence had put their captains and crews aboard the swiftest of the dragons of the niru , and kept murat himself aboard temeraire , but he was mindful that not all the french dragons might have been harnessed from the shell , and might not feel the intensity of attachment to their captains which ordinarily served to render a captured beast meek .