six
o'clock
`` What address did they leave ? '' he inquired , annoyed at the neat manner in which they had escaped his vigilance . `` They left no address , m ` sieur . They received a telegram just after six o'clock recalling them to Paris immediately . Fortunately , there was one two-berth compartment vacant on the train . '' Walter turned away full of chagrin . He had been foolish to lose sight of them .