“Well, what have you learned?” Chief Hadley asked, when the two detectives entered and rejoined the group in the basement. “You have been gone long enough to have discovered something.” “Enough to further confirm Doctor Nolan’s opinion,” Nick replied, a bit dryly. “The body was taken away by four men who came in a wagon.” “Ah!” Doctor Nolan exclaimed. “I was reasonably sure of it.” “There is no other evidence worthy of mention,” Nick added. “It may be well, chief, to have an officer inquire at the dwellings in the side street. The crooks possibly were heard, or even seen, without the truth being suspected.” “I will attend to it,” Hadley nodded, while they returned to the office of the undertaker. “There is nothing more to be learned here,” said Nick. “I will look deeper into the case, however, and will report to you later.” “Do so, Nick, by all means.” “Regarding that vial, Doctor Nolan. I want you to let Chick take it for a few hours,” Nick added, turning to the physician. “I want an analysis of its contents, or the nature of it to be positively determined. I will be responsible for its safe return.” “That’s good enough for me, Carter,” Doctor Nolan readily assented. “Chick will call at your office for it later in the day.” “Very well.” Nick did not defer his departure to further discuss the matter. He left Chief Hadley and the coroner to proceed as they saw fit, and Herman Fink in quite abject consternation over the gruesome calamity that had befallen him. “We now will hunt up a directory,” Nick remarked, walking up the street with Chick and Patsy. “I decided not to consult the one in Fink’s office.” “It would have led Hadley to suspect that we are wise to something,” smiled Chick. “Surely.” “What have you picked up?” questioned Patsy, surprised. Chick informed him, ending just as they arrived at a corner drug store, into which Nick led the way. A city directory supplied him with the information he was seeking. “Here we have it,” said he, while Chick and Patsy eagerly read the address to which he pointed. “The Dabney Private Medical College.” “By Jove, there is no question about it,” Chick declared. “Private--that was the word that bothered me,” Nick added. “The first two words looked like a single exceedingly long one. This certainly does settle it. Come on. We’ll not wait for breakfast. We’ll find out what’s doing in this Dabney Private Medical College. There shall be nothing too private for us to butt into, Chick, take my word for that.” CHAPTER III. THE EMPTY BOX. Gifted with more than ordinary intuition, as well as a remarkably keen perception resulting from years of trained experience, Nick Carter already felt sure that the case engaging him had features that did not yet appear on the surface, and that it might prove to be one of the strangest cases on record.