viii
CONTENTS
'
CHAPTER
PAGE
,
17. SMALL CURRENTTECHNIQÜE…....................… 387
Introduction.
Electroscopes,—Principle of the electroscope. Various
_
forms of electroscopes. Adjustment of an electroscope. The natural
leak of an electroscope. Inserting a new leaf. Cahbratron of an
electroscope. Electrometers,—Principle and use of the quadrant electrometer.
Description of the instrument. Electrometer connections.
‘
Calibration for voltage measurements.
Calibration for current
measurements. Capacity of the quadrant system. Measurement of
"
quantity of electricity.‘ Various forms of electrometers. D.C.
ompliers. [onization chambem,—Ionization chambers for use With
.,
_
x-rays.
Ionization chambers for use With gamma rays.
Iomzat10n
chambers for use with cosmic rays. Experiment.
18. THE DETECTION or PARTICLES...................... 418
Introduction.
Shallow ionization
principle of shal*
low Chambers. -— Construction of shallow chambers.
Differential
’
chambers.
Notes concerning the linear amplier. Scale-of—two
'
counter
circuits.
Counter tubes,—The principle of counter tubes.
Types of counter tubes. Counter tube circuits. The background
'
count.
The counting—rate voltage curve. The sensitivity of coun—
_ters.
The efciency of counting. The manufacture of Geiger—
Müller
counter
tubes. Expansion chamhw,—The principle of
expansion chambers. The design and operation __of expansion
_
chambers. Some of the features of drop—tracks.
:
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19. NOTES ON HIGH VOLï;AGE TECHNIQUE.
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.
.
.
442
ï
The measurement of high voltage,—Sphere gâps.
Resistance types.
’
.
Generat1ng voltmeters.
Miscellaneous.
Indirect measurement of
voltages. Same problems of insulation,—Corona.
Tran'
_
‘smon regions. X-ray lament transformers.
'
PROBLEMS
450
TABLES
459
INDEX
473
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