The deductive method of solving the problem of a mysterious crime employed by Chapman was not alone interesting to the Chief of Detectives, but appeared wonderful in the correctness of the conclusions obtained. He therefore gave eager attention to what Chapman communicated to him while seated in the Chief’s private office on the evening of the day that Burton visited the office of J. Dunlap to secure his private correspondence and documents. “In the first place, Chief, as soon as I learned the details of this Malloy crime, I decided that the perpetrator of it was of the negro race,” said Chapman, methodically arranging a number of slips of paper on the Chief’s desk, at which he sat confronting O’Brien on the opposite side. “How did you arrive at that decision?” said the detective. “Well, as you are aware, for you laughed at me often enough when you ran across me with my black associates, I ‘slummed’ among the negroes for months to gain some knowledge of the negro nature”. “Yes, I know that and often wondered at your persistent prosecution of such a disagreeable undertaking,” said O’Brien. “I learned in that investigation that beneath the surface of careless, thoughtless gaiety and good nature there lies a tremendous amount of cruelty and brutal savagery in the negro nature; that dire results have been caused by a misconception of the negro character on this point to those associated with them; that while sensual satiety produces lassitude in other races, in the negro race it engenders a lust for blood that almost invariably results in the murder of the victim of a brutal attack. I checked the correctness of my conclusions by an examination of all obtainable records and completely verified the accuracy of my deduction.” “That had not occurred to me before,” said the Chief frankly; “now that you mention it, I think from the record of that crime, as it recurs to me at this moment, that your statement is true.” “The next step was to look for the particular individual of the negro race who could fit in with the trifling evidence in your possession, which you so readily submitted to me. From the mold taken by your men of the criminal’s foot-prints it is evident that his feet were small and clad in expensive shoes. In the shape of the imprints I find corroboration of my premise that the author of the crime was of the negro race. The fragment of finger nail embedded in the girl’s throat, under a microscope reveals the fact that, while the nail was not free from dirt, it had recently been under the manipulation of a manicure and was not of thick, coarse grain like a manual laborer’s nails,” said the amateur detective glancing at his notes. “Yes, I agree in all that, Mr. Chapman. Go ahead; what follows?” remarked O’Brien.