on the letter which he had found in old Mr Longestaffe’s drawer.  He had found it in an envelope, addressed by the elder Mr Longestaffe to Messrs. Slow and Bideawhile, and he had himself posted this letter in a pillarbox near to his house.  In the execution of this manoeuvre, circumstances had greatly befriended him.  He had become the tenant of Mr Longestaffe’s house, and at the same time had only been the joint tenant of Mr Longestaffe’s study,—­so that Mr Longestaffe’s papers were almost in his very hands.  To pick a lock was with him an accomplishment long since learned.  But his science in that line did not go so far as to enable him to replace the bolt in its receptacle.  He had picked a lock, had found the...