midnight
they are only changing watch , '' replied Ugo . `` I do not remember this trumpet , '' said Emily , `` it is a new custom . '' `` It is only an old one revived , lady ; we always use it in time of war . We have sounded it , at midnight , ever since the place was besieged . '' `` Hark ! '' said Emily , as the trumpet sounded again ; and , in the next moment , she heard a faint clash of arms , and then the watchword passed along the terrace above , and was answered from a distant part of the castle ; after which all was again still . She complained of cold , and begged to go on .