Finally, realizing that the complaints demanded attention, Otto Failmerzger, chief clerk of the department, hung on the hook an order to the foreman of the gang charged with the care of gutters and sewers, to remove the supposed obstruction in the sewer without delay. On the following morning--Tuesday, May 22nd--the foreman in question, Nicholas Rosch, accompanied by two of his assistants, John Finegan and William Michaels, went to the locality indicated. They found that the ditch on the east side of Evanston Avenue was partially filled with water, which was constantly creeping from a damaged fire plug. The fall of water here was to the north. About twenty feet north of the fire plug was a catch-basin into which the water from the ditch was supposed to flow, just as it flows into them in sections of the city that are paved. At this point, however, the sand had rolled down from the roadway into the open ditch, damming up the water so that it could not escape into the basin. One glance at the ditch convinced Foreman Rosch that this was the source of the trouble, and procuring their shovels, the three men went to work with a will to throw out the moist sand. It was a slow and laborious job, and it was well on towards four o'clock when they reached the immediate vicinity of the catch-basin. The latter, as will be seen in the illustration, was circular in form, built of brick, and with a heavy wooden top on a level with the street. About two feet below the top was an opening in the side of the brick wall to the southwest. In this a barred iron grating was set, through which the water from the ditch was supposed to flow. With the exception of this side, which was open to the bottom of the grating, the circular brick basin was surrounded by dirt almost to the street level. The locality was precisely one mile north of the spot where the bloody trunk had been found, the same roadway leading directly to the catch-basin and almost directly to the neighborhood of O'Sullivan's ice-house whither Dr. Cronin had been summoned by the mysterious messenger. [Illustration: THE CATCH-BASIN, SHOWING FIRE-PLUG AND DITCH.] "MURDER WILL OUT." The laborers wondered, as they shoveled the sand out of the ditch, what it was that caused the terrible stench that pervaded the atmosphere. It was indescribably strong and noisome, and more than once they were almost compelled to cease their work. Yet, although they searched around and examined the ground for a square block, they could find nothing to which it could be attributed. At last the ditch was cleaned out, and the foreman concluded to take a look into the catch-basin before quitting for the night. Accordingly, getting down on his hands and knees, he peered through the iron grating. In the darkness he could discern something white apparently floating in the water. "There's a dog in here" he called out "and that's what has been making this stench."