Our readers are now ready to ask if we have discovered the machinery or instrumentality by which these girls make the sounds. In answer, we say that our investigation is conclusive that these sounds are entirely at the control of these girls, and that we have placed them in situations where they could not rap at all. And if, after all this, we have invented several modes by which the rappings can be made as successfully as by them, we think we have discovered enough. During each of our two visits, we noticed, by very cautious and careful inspection, one interesting and significant fact--that each rap was attended with a slight movement of the person of the rapper, and that a very distinct motion of the dress was visible about the right hypogastric region. While watching this point the girl noticed us, and immediately rose, went to the window, and dropped the curtain to darken the room, which was on the north side of the building, and full dark enough before. When she sat down she drew her shawl over this part of her person. This was on the first visit. On the second visit, we were soon discovered watching this movement again, and she rose and procured a shawl with which she covered her person as before. We do not pretend to decide that this movement had any direct connection with the instrument by which she rapped upon the floor; if so, it was very clumsy and awkward, for we have devised a mode of rapping that involves no such motion, and which we will shortly explain. It may have been that this movement was connected with the device for rapping upon the table. We are of opinion that when they rapped upon the table, it was upon the under side of the table-top and not about their feet. They did not, and evidently could not, rap upon the table without sitting closely up to the table. If this conjecture, as to the rap under the table-top, is right, the movement we saw is easily accounted for. Be it so, or be it not, we have invented a contrivance which raps upon the under side of the table-top, and which involves precisely the motion we discovered. It requires but little exercise of ingenuity to contrive means of producing these sounds. It has been stated that a relative of these girls has made a public statement under oath, that they produce the raps with their toes, in a peculiar manner acquired by long practice. The public papers tell us that electro-magnetism has been employed to carry out this fraud. The snapping of the joints has been resorted to by another; and indeed we can easily imagine a variety of ways in which these sounds are, or may be produced. The Fox girls rapped upon neither of these plans. The sound was machine-like, and too loud for a sound that could be made by striking the naked or unarmed toe upon the floor, and entirely too loud for, and differing in character from, the snapping of the joints, and as to electro-magnetism, it was entirely out of the question in this case.