Rack
2 of the 7 encyclopedias on this shelf carry an entry for Rack. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
an apparatus for the judicial torture of criminals or suspected persons. It consisted of a large, open, wooden frame, within which the person to be tortured was laid on his back on the floor, with his wrists and ankles fastened by cords to two rollers at the end of the frame. These rollers were then drawn or moved in opposite directions till the body rose to a level with the frame. Interrogations were then put, and if the prisoner refused to answer, or if his answers were not considered satisfactory, the rollers were further moved, until at last the bones of the sufferer were forced from their sockets. In gearing, a toothed bar whose pitch line is straight, adapted to work into the teeth of a wheel for the purpose of changing rectilinear into circular motion, motion, or vice versa. This contrivance is called a rack-and-pinion, and the motion so imparted rack-and-pinion motion. In horology, a steel piece in the striking part of a clock. In lace, a certain length of lace-work counted perpendicularly, and containing 240 meshes. In metallurgy, an inclined frame or table, open at the foot, and upon which metalliferous slimes are placed and exposed to a stream of water, which washes off the lighter portions. Nautically, (1) A frame of wood with belaying-pins, or a row of blocks for fair-leaders, or a row of sheaves for reeving the running-rigging. (2) A frame with holes for round shot. (3) A box in which the halyards are coiled away.
Aiton's Encyclopedia (1910)
an instrument of torture used in the Middle Ages to extort a confession or a promise. It consisted of a wooden frame somewhat longer than a bedstead with a roller at each end. The victim of torture was laid on his back on this frame, the ankles were tied by a cord to one roller and the wrists to the other. By turning the rollers with pins or handspikes and winding up the cords, the victim's body would be lifted and his limbs could be stretched beyond endurance, even to tearing them out of their sockets. A twinge or two of such mortal agony would extort the hiding place of treasure, wife, or child, or secure the assent to any statement the persecutor might desire to place in his mouth. Civilized nations wisely forbid the use of torture even to get at the secrets of the vilest offenders. In fact, in English-speaking countries, the law does not compel one to testify against himself or a wife against her husband.