Ionization Chamber of Victor Hess |
|
|
This particular chamber was one of seven that were
built for Victor Hess at Measurements were performed using paired chambers.
One chamber contained the sample being analyzed and the other compensating
chamber contained only nitrogen. The latter chamber was used to account
for background. The central
electrodes of the two chambers were connected to each other and the fiber
of a Lindemann electrometer. The chamber walls (outer electrodes) were
given opposite potentials. The wall of the chamber containing the breath
sample was given a +135 V potential relative to its central electrode,
while the wall of the compensating chamber was given a – 135 V
potential. |
 |
 |
The diagram to
the left indicates the electrical circuit of the system. |
|
Filling
of the chamber was accomplished as follows. The chamber was evacuated and
then connected via a drying tube to a spherical glass flask containing the
breath sample. This tube contained a desiccant to remove water from the
breath sample as it was transferred to the ionization chamber. Another
tube from the sample flask was inserted into a jar containing tap water.
When the stopcocks were opened, the breath sample was pushed into the
evacuated chamber by the water as it replaced the sample in the flask. If
the sample was not sufficient to fill the four-liter chamber, aged
nitrogen was added until the chamber reached atmospheric pressure. To see the electrometer used by Victor Hess, click here. |
|
|
References Hess, V. F. and McNiff, W.T. Quantitative Determination of the Radium Content of the Human Body and of the Radon Content of Breath Samples for the Prevention and Control of Radium Poisoning in Persons Employed in the Radium Industry Am. J. Roentgenol. And Radium Therapy, 57: 91-102, 1947. |
|