A brass drum sits horizontally between anterior axle post and posterior mechanical drive box. The instrument is mounted on a large ovoid metal base with an adjustable front foot with screw for leveling the instrument. The instrument is mechanically driven. A governor maintains the brass drum at a constant speed.
Accession Number: 2011.psy.68
Primary Materials: Brass, Metal
Manufaturer’s label engraved on the top “Pirard et Coeurdevache, Constructerus, 7 rue Blainville, Paris.
Height = 20, Width = 15.5, Length = 46.5
A kymograph is a clock-driven drum that rotates at a very precise rate in order to provide a continuous surface for recording experimental data. The revolving drum would have been wrapped with smoked paper which was marked by a signal marker. A signal from a timekeeping device would also have been recorded alongside the experimental data in order to provide a time reference.
Pirard et Coeurdevache, Constructerus, 7 rue Blainville, Paris
Late 19th Century or Early 20th Century
Department of Psychology, University of Toronto
Titchener, E. B. (1918). Experimental Psychology, a Manual of Laboratory Practice: Volume I, Quantitative Experiments, Part II. Instructor’s Manual. New York: MacMillan, Vol. 1, pp. 172-176.
Psychologists first used kymographs for recording blood pressure. Experimental psychologists adopted the kymograph as an instrument for recording various time-related events: response times, stimulus presentations, muscle exertion and tuning fork vibrations. The preparation of smoked paper, an art in itself, consisted of placing a blank sheet of paper over a stand and exposing it to petroleum lantern fumes.The experimenter then wrapped the smoked paper around the drum. The signal maker would contact the drum as it rotated, leaving a line record. Following the recording, the experimenter varnished the paper for permanent keeping (Titchener, 1918). Two of August Kirschmann’s students at the University of Toronto refer directly to one of the earliest horizontal kymographs used in the laboratory, in a study on the estimation of time intervals. (Shaw and Wrinch, 1900).