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rhythm apparatus
rhythm apparatus

rhythm apparatus

Datecirca 1903
Inventory NumberWJ0112
ClassificationAcoustic Instrument
Subject
    User Robert MacDougall 1866 - 1939
    Cultural Region
      Place of Origin
        Dimensions34 x 65 x 43 cm, 33 lb. (13 3/8 x 25 9/16 x 16 15/16 in., 15 kg)
        pulley wheel: 12.5 cm (4 15/16 in.)
        Material
          Accessorieswooden disks (41); steel and brass fittings; wooden box for storing accessories
          DescriptionA device consisting of four parallel metallic shafts mounted on two pairs of metallic stands on a wooden base. Three shafts share one pair of stands while the fourth has a pair for itself.

          The thicker shaft on the shared stands holds the bases of fifteen numbered hammers at regular intervals which extend across to the shaft on the other stands. On that shaft, the hammer heads slide on wooden disks that gradually increase in diameter until they suddendly end in a gap with a metallic anvil. This is the only shaft with a mechanism that allows it to rotate and can be connected to a motor by a pulley wheel.

          A third shaft, connected to the same stands as the hammer bases, has vertical holders for each hammer so they can be lowered and raised simultaneously from the disks they are sliding on. The fourth shaft is simply the axis on which this lowering mechanism rotates.
          Signedstamped on wooden base: H. SUMNER / CAMB. MASS.
          FunctionThis is an instrument that was designed for studying the perception of rythm in people. The intention was to eliminate all other aspects of music such as varying tones and a recognizable melody. The way to accomplish this is to have a set of identical hammers that can be made to fall at set intervals and from varying heights.

          The hammers are held in a horizontal position by their bases being attached to a shaft parallel to the rotating one. Their heads slide on rotating wooden disks that increase in diameter to suddenly end in a gap with a metallic anvil, so the hammer produces a sound by hitting it. There are many disks with different diameters to choose from so that the loudness can be varied, and they can be rotated to any angle, controlling the exact moment in a cycle when the hammer hits the anvil. Since there are fifteen hammers, the rythmic sounds that are produced can be very complex, and the purpose of the instrument was precisely to test the limits of the perception of rythm.

          The hammers can be raised and lowered simultaneously so that the motor can be set in motion and stabilized before the experiment begins.

          An extensive description of this instrument as well as the results of research conducted with it can be found in Robert McDougall's "The Structure of Simple Rhythm Forms" article available online at Project Gutenberg here.

          ProvenanceFrom the Department of Psychology, Harvard University.
          spare gearboxes (3) for marginal oscillator
          Department of Physics, Harvard University
          Date: mid 20th-late 20th Century
          Accessories: five odd knobs, each with some sort of arrow showing which way it is pointing
          Object number: 2004-1-0408g
          rheostats in a storage box.
          Object number: RS0173
          rheostats in a storage box
          Object number: RS0191
          counting mechanism
          American
          Date: 1850-1900
          Object number: 1998-1-0154
          apparatus for measuring angle of incidence
          Benjamin Martin
          Date: circa 1765
          Object number: 0087
          sectional model of a steam engine cylinder
          Max Kohl A. G.
          Date: circa 1910
          Object number: 6905
          model of two-storey gantry
          Andreas Koehler
          Date: circa 1977
          Object number: 2003-1-0279
          Barth's belt slide rule
          Carl G. Barth
          Date: dated 1921
          Object number: 1990-5-0006
          marginal oscillator for NMR
          Department of Physics, Harvard University
          Date: mid 20th-late 20th Century
          Accessories: variety of spare parts cataloged as 2004-1-0408c-g
          Object number: 2004-1-0408a
          piece for another apparatus
          Object number: WJ0599