column for falling bodies experiment
Date: circa 1850
Inventory Number: DW0316b
Classification: Demonstration Apparatus
Subject:
Maker: Breton Frères (fl. 1843 - 1884)
Cultural Region:
Place of Origin:
Dimensions:
column: 100 × 31 × 12 cm (39 3/8 × 12 3/16 × 4 3/4 in.)
assembled: 100 × 55 × 27.8 cm (39 3/8 × 21 5/8 × 10 15/16 in.)
Accessories: box of marbles (c)
Description:
This instrument consists of a high column on top of which is a platform held in place by an elegantly turned urn filial. The platform supports at its end a funnel in which one of the small marbles is put. A hole pierced through the platform, under the funnel, lets the marble fall. When the latter fall, it hits an adjustable inclined board. A semi-circular graduated circle, divided in two quadrants of 90 degrees (marked in single degrees) determines the board's angle of inclination. On that same graduated circle is fixed a box into which the marble will land if properly adjusted. A hook opens the back side of the box to remove the marble. The instrument is supported by a rectangular base with four leveling screws, also decorated with an urn finial. The marbles are stored in a small box.
Signedon plate: BRETON FRERES / Paris rue Dauphine 25
FunctionThis demonstration apparatus is to show that when a ball (or marble) is thrown against a hard surface at an angle, it rebounds in the opposite direction with the same angle. Just as light does when hitting a mirror, the marble's angle of incidence equals its angle of reflection.