to its original pressure. In other words, _the heat of compression and
the cold of expansion are in degree equal_.

Experiments made by M. Regnault and others on the influence of heat on
pressures and volumes of gases have enabled us to fix the absolute zero
of temperature as -461 degrees Fahrenheit. This point, 461 degrees below
zero, is the theoretical point at which a volume of air is reduced to
nothing. The volume of air at different temperatures is in proportion to
the absolute temperature, and on this basis Box gives us the following
table:

TABLE l.--OF THE VOLUME AND WEIGHT OF DRY AIR AT DIFFERENT TEMPERATURES
UNDER A CONSTANT ATMOSPHERIC PRESSURE OF 29.92 INCHES OF MERCURY IN THE
BAROMETER (ONE ATMOSPHERE), THE VOLUME AT 32° FAHRENHEIT BEING 1.

Temperature Volume in Weight of a
in degrees. cubic feet. cubic foot in lb.
32 1.000 0.0807
42 1.020 0.0791
52 1.041 0.0776
62 1.061 0.0761
72 1.082 0.0747
82 1.102 0.0733
92 1.122 0.0720
102 1.143 0.0707
112 1.163 0.0694
122 1.184 0.0682
132 1.204 0.0671
142 1.224 0.0660
152 1.245 0.0649