about ten o'clock
I refilled my acquaintance 's mug , pressed a sovereign upon him -LRB- in honesty I must confess that he was loath to take it -RRB- , and departed with the pigtail coiled neatly in an inner pocket of my jacket . I entered the house in Wade Street by the side door , and half an hour later let myself out by the front door , having cast off my dockland disguise . It was not until the following evening that I found leisure to examine my strange acquisition , for affairs of more immediate importance engrossed my attention . But at about ten o'clock I seated myself at my table , lighted the lamp , and taking out the pigtail from the table drawer , placed it on the blotting-pad and began to examine it with the greatest curiosity , for few Chinese affect the pigtail nowadays . I had scarcely commenced my examination , however , when it was dramatically interrupted . The door bell commenced to ring jerkily . I stood up , and as I did so the ringing ceased and in its place came a muffled beating on the door .