4:35
`` Last Monday Mr. Neville St. Clair went into town rather earlier than usual , remarking before he started that he had two important commissions to perform , and that he would bring his little boy home a box of bricks . Now , by the merest chance , his wife received a telegram upon this same Monday , very shortly after his departure , to the effect that a small parcel of considerable value which she had been expecting was waiting for her at the offices of the Aberdeen Shipping Company . Now , if you are well up in your London , you will know that the office of the company is in Fresno Street , which branches out of Upper Swandam Lane , where you found me to-night . Mrs. St. Clair had her lunch , started for the City , did some shopping , proceeded to the company 's office , got her packet , and found herself at exactly 4:35 walking through Swandam Lane on her way back to the station . Have you followed me so far ? '' `` It is very clear . '' `` If you remember , Monday was an exceedingly hot day , and Mrs. St. Clair walked slowly , glancing about in the hope of seeing a cab , as she did not like the neighbourhood in which she found herself .