midnight
And it is better , so that Belisarius may be quite safe , that he only enter the meeting when he sees my Moor Syphax in the niche before the house behind the statue of Petrus . He may also place a few of his guards in front of the house . In case of need , they can protect him , and bear witness in his favour . He is not capable of much feigning ; he must only join the meeting shortly before midnight ; thus he will have no need to speak . Our guards will wait in the Grove of Constantinus , at the back of Photius 's house . At midnight -- the trumpet sounds when the guard is relieved , and you know that it can be distinctly heard -- we shall break in . Belisarius , therefore , need not undertake the dangerous task of giving a signal . ''