-22- 50 | 0.2377 | Regnault |
| 0-100 | 32- 212 | 0.2374 | Regnault |
| 0-200 | 32- 392 | 0.2375 | Regnault |
| 20-440 | 68- 824 | 0.2366 | Holborn and Curtis |
| 20-630 | 68-1166 | 0.2429 | Holborn and Curtis |
| 20-800 | 68-1472 | 0.2430 | Holborn and Curtis |
| 0-200 | 32- 392 | 0.2389 | Wiedemann |
|____________|____________|_______________|____________________|

This value is of particular importance in waste heat work and it is
regrettable that there is such a variation in the different experiments.
Mallard and Le Chatelier determined values considerably higher than any
given in Table 28. All things considered in view of the discrepancy of
the values given, there appears to be as much ground for the use of a
constant value for the specific heat of air at any temperature as for a
variable value. Where this value is used throughout this book, it has
been taken as 0.24.

Air may carry a considerable quantity of water vapor, which is
frequently 3 per cent of the total weight. This fact is of importance in
problems relating to heating drying and the compressing of air. Table 29
gives the amount of vapor required to saturate air at different
temperatures, its weight, expansive force, etc., and contains sufficient
information for solving practically all problems of this sort that may
arise.

TABLE 29

WEIGHTS OF AIR, VAPOR OF WATER, AND SATURATED MIXTURES OF AIR AND VAPOR
AT DIFFERENT TEMPERATURES,
UNDER THE ORDINARY ATMOSPHERIC PRESSURE OF 29.921 INCHES OF MERCURY

Column Headings:
1: Temperature Degrees Fahrenheit
2: Volume of Dry Air at Different Temperatures, the Volume at 32 Degrees
being 1.000
3: Weight of Cubic Foot of Dry Air at the Different Temperatures Pounds
4: Elastic Force of Vapor in Inches of Mercury (Regnault)
5: Elastic Force of the Air in the Mixture of Air and Vapor in Inches of
Mercury
6: Weight of the Air in Pounds
7: Weight of the Vapor in Pounds
8: Total Weight of Mixture in Pounds
9: Weight of Vapor Mixed with One Pound of Air, in Pounds
10: Weight of Dry Air Mixed with One Pound of Vapor, in Pounds
11: Cubic Feet of Vapor from One Pound of Water at its own Pressure in
Column 4
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