Reflection of Particles
From the 1881 catalogue of James W. Queen of Philadelphia:
"Apparatus to Illustrate the Reflexion of Motion. Consisting of
a semicircular table of cherry, a marble slab for reflector, a spring pistol,
ivory ball, and pocket to catch the ball after the rebound. Edge of table
graduated to show the relation between the angles of incidence and reflexion.
... $20.00 ."
The apparatus above is in the Garland Collection of Classical
Physics Apparatus at Vanderbilt University. The note in the reference also
illustrates two very similar pieces of apparatus: John Tyndall's demonstration
to show the specular reflection of visible light, and his apparatus for
showing the specular reflection of sound. It seems that when introducing
students to specular reflection, a particle model describes the situation
well. Newton thought so, too.
The apparatus below is at Colby College in Waterville,
REF: Thomas B. Greenslade, Jr., "Nineteenth Century Textbook
Illustrations XXXIII: Reflection Spectrometers", Phys. Teach., 18,
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