midnight
But again we were absolutely blind . It was the second week of May , and since , in spite of continued fine weather , our unknown terror remained in the seclusion of his hiding-place , wherever it might be , I had persuaded Forrest to come with me for a run one afternoon as far as Cambridge , proposing to return after sunset . The roads were beginning to be a little dusty , but altogether we had a very pleasant journey without any incident of note . We left the university town about nine , reckoning upon getting home comfortably before midnight . There was a bright slice of moon shining , and we did the dozen miles before reaching Royston at a decent pace . We went slowly over the hilly road out of Royston and had passed over the worst of it , and I had just put on a higher speed , when I fancied I heard the distant hum which once heard could never be mistaken for anything else . Forrest heard it at the same time as myself .