The phenomenon of elongation is fairly common at a spiritualist seance. It might be described as the stretching out of the medium’s body; his height may increase from three inches to a foot.
There are accounts of the phenomenon by creditable witnesses in the social and scientific world describing the elongations of Herne, Home, and Morse. Such manifestations usually occur when the light was low, but there are several exceptions. When describing the elongation of Home Sir Lindsay stated, “Home looked as if he was pulled up by the neck, the muscles seemed in a state of tension.
He stood firmly upright in the middle of the room, and before the elongation commenced I placed my foot on his instep.” The same witness described Home’s increase in height on this occasion as eleven inches. Most accounts describe a violent swaying motion on the part of the medium as preceding the elongation, which some critics have regarded as a convenient mode of covering the use of mechanism that might be concealed in the medium’s boot. A.G.H.
Source: 81, 141.