On looking around, horrible was the sight which met the officers' eyes. In one corner of the room was a nearly white child, bleeding to death. Her throat was cut from ear to ear, and the blood was spouting out profusely, showing that the deed was but recently committed. Scarcely was this fact noticed, when a scream issuing from an adjoining room drew their attention thither. A glance into the apartment revealed a negro woman holding in her hand a knife literally dripping with gore, over the heads of two little negro children, who were crouched to the floor, and uttering the cries whose agonized peals had first startled them. Quickly the knife was wrested from the hand of the excited woman, and a more close investigation instituted as to the condition, of the infants. They were discovered to be cut across the head and shoulders, but not very seriously injured, although the blood trickled down their backs and upon their clothes. The woman avowed herself the mother of the children, and said that she had killed one and would like to kill the three others, rather than see them again reduced to slavery! By this time the crowd about the premises had become prodigious, and it was with no inconsiderable difficulty that the negroes were secured in carriages, and brought to the United States District Court-rooms, on Fourth Street. The populace followed the vehicle closely, but evinced no active desire to effect a rescue. Rumors of the story soon circulated all over the city. Nor were they exaggerated, as is usually the case. For once, reality surpassed the wildest thought of fiction. The slaves, on reaching the marshal's office, seated themselves around the stove with dejected countenances, and preserved a moody silence, answering all questions propounded to them in monosyllables, or refusing to answer at all. Simon is apparently about fifty-five years of age, and Mary about fifty. The son of Mr. Marshall, who is here, in order, if possible, to recover the property of his father, says that they have always been faithful servants, and have frequently been on this side of the river. Simon, Jr., is a young man, about twenty-two years old, of a very lithe and active form, and rather a mild and pleasant countenance. Margaret is a dark mulatto, twenty-three years of age; her countenance is far from being vicious, and her senses, yesterday, appeared partially stultified from the exciting trials she had endured. After remaining about two hours at the marshal's office, Commissioner Pendery announced that the slaves would be removed to the custody of the United States Marshal until nine o'clock Tuesday morning, when the case would come up for examination.