For the third test, final pressure to be 0.5 of differ-
ence between initial and atmosphere.
For the fourth test, final pressure to be 0.7 of differ-
ence between initial and atmosphere.
For the fifth test, final pressure to be 0.9 of differ-
ence between initial and atmosphere.
Cooling- jacket to be cut out.
Each test should be of 15 to 20 minutes duration,
the conditions of the test to exist for five minutes
before the first observation is taken.
The following observations should be taken every
two minutes: initial, intermediate, and final pressure.
The following should be taken every four minutes:
pressure and temperature in each calorimeter. The



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32 ENGINEERING LABORATORY PRACTICE.
weight of condensed steam should be taken once for
the test, and the barometer read twice during the test.
Use only enough cooling water on the condenser to
condense the steam. Be sure that the pressure-gages
are not subjected to a pressure beyond their range.
The Report should include:

1. Sketch and description of apparatus.
2. Sketch and dimensions of orifice.
3. Tabulated statement of results for each test.
4. A curve having ratio of final absolute pressure
to initial absolute pressure for abscissae and flow of
steam in pounds per hour for ordinates.
In order to determine the effects of different per-
centages of moisture in the steam repeat the above
series, manipulating the cooling-jacket to secure in-
creasing amounts of moisture in the steam.
