One of the first things to be determined was whether the blood on the floor of the cottage and that found in the trunk was identical. Dr. Brandt and Dr. Hectone were sent for, and for the balance of the day they were busily engaged in making examinations and microscopic comparisons. By night they were in a position to declare that two things had been definitely established. First, that the blood found in the Carlson cottage was that of a human being, and second, that, so far as an expert examination by the most approved methods had gone, it went to prove that the blood taken from the trunk and that taken from the house came from one and the same body. This feature of the tragedy created the greatest interest in medical circles, from the fact that it was the first case on record in which such a comparison had been attempted. "I examined the blood found in the trunk," said Dr. Brandt on the evening of the day in question, "soon after it was found and determined that it was human. The first thing to do was to determine whether the spots in the house were also human blood." "How can you tell whether certain blood is that of a human being, or of some animal?" he was asked. "Only by the size of the corpuscles. They are large and compressed on either side. It can be done only by means of a powerful microscope, and even with this aid none but an expert can tell. By submitting the blood to this test it was found to be human blood. This settled, the next thing of importance was to find out if the two specimens of blood bore any resemblance." "Can you tell to a certainty whether two drops of blood come from the same body?" "You cannot; but if they bear certain marks of resemblance the inference is pretty strong. You must bear in mind that the blood in both cases was taken from wood. That found in the trunk was diluted with water. After diluting the blood taken from the floor of the house sufficiently to make it of the same consistency, or as near as may be, with that from the trunk, we submitted them both to the microscopic test----" "And found?" "That the points of resemblance were marked. The pigment crystals were exactly alike." "From which you inferred----" "That the blood found in the trunk and that taken from the floor of the house came from the same person." "Do you think, Doctor, that it is the blood of Dr. Cronin?" "There is not the least doubt of it in my mind. It is almost certain that the doctor's body was in that trunk. If this is so, there can be little doubt that he met his death in the house on Ashland avenue." THE CARLSONS TELL THEIR STORY.