three o'clock
`` Now do tell me what we are to do for poor , poor Fly . Do you think David is guilty , and that he has got Fly to promise not to tell ? '' `` Yes , that is what I think . David must be found , and got to confess , and so release Fly of her promise before three o'clock . David is a dreadful boy to find when he takes it into his head to hide on purpose ; but I must look for him , and in the meantime will you guard your father , Polly ? '' `` As a dragon , '' said Polly . `` You may trust me about that at least .