(Chronograph nach Wundt.)
Description: This device claims to be capable of time measurement
to .0001 sec. It is a kymograph drum driven by a "powerful"
spring motor and mounted horizontally on low-friction rollers.
The speed regulation of the spring motor occurs through settable
wind-vanes and the use of 60 Kg. of lead weights, attached to a
chain which runs through the spring motor housing. The timing
occurs through the provision of a 500 Hz tuning fork which marks
a sine wave on the roller with a period of .002 seconds. The
tuning fork has an independent electromagnetic excitation source,
presumably best supplied from a house/wall current, which is
initiated by a secondary fork. The 620 mm circumference drum can
be rotated in .1 sec, thus spreading out each of 50 cycles over
12.4 mm, and presumably permitting accurate measurement to .6 mm,
giving the accuracy of .0001 sec. The apparatus includes a lever
(H) which allows the drum and motor to be quickly stopped.
In order to provide a time measurement which is longer than a
few seconds, the writing-bristle moves in a spiral track on the
paper. To do this, a counterbalanced sled-like device holds the
writing-bristle which marks the cycles of the tuning fork on the
carboned paper. Timed events are marked by one of three
electromagnetically driven pens attached to the sled. (Expanded
caption Copyright 1998, Edward J. Haupt)
(Source: Wundt (190.). Physiologische Psychologie)
Source of illustration: Zimmermann, E. (1903). XVIII. Preis-
Liste über psychologische und physiologische Apparate
(p. 66-67). Leipzig: Eduard Zimmermann.
DESCRIPTORS:
Type: Component, timing.
Stimulus: N/A
System: N/A
Output: time marking