iler to a vertical outlet,
water may collect at the lower end of the uptake pipe and be blown
upward in a spray which will not be carried away by the steam owing to a
lack of velocity. A sample taken from the lower part of this pipe will
show a greater amount of moisture than a true sample. With goose-neck
connections a small amount of water may collect on the bottom of the
pipe near the upper end where the inclination is such that the tendency
to flow backward is ordinarily counterbalanced by the flow of steam
forward over its surface; but when the velocity momentarily decreases
the water flows back to the lower end of the goose-neck and increases
the moisture at that point, making it an undesirable location for
sampling. In any case, it should be borne in mind that with low
velocities the tendency is for drops of entrained water to settle to the
bottom of the pipe, and to be temporarily broken up into spray whenever
an abrupt bend or other disturbance is met.

[Illustration: Fig. 19. Illustrating the Manner in which Erroneous
Calorimeter Readings may be Obtained due to Improper Location of Sampling
Nozzle

Case 1--Horizontal pipe. Water flows at bottom. If perforations
in nozzle are too near bottom of pipe, water piles against
nozzle, flows into calorimeter and gives false reading.
Case 2--If nozzle located too near junction of two horizontal
runs, as at a, condensation from vertical pipe which collects at
this point will be thrown against the nozzle by the velocity of
the steam, resulting in a false reading. Nozzle should be
located far enough above junction to be removed from water kept
in motion by the steam velocity, as at b. Case 3--Condensation
in bend will be held by velocity of the steam as shown. When
velocity is diminished during firing intervals and the like
moisture flows back against nozzle, a, and false reading is
obtained. A true reading will be obtained at b provided
condensation is not blown over on nozzle. Case 4--Where
non-return valve is placed before a bend, condensation will
collect on steam line side and water will be swept by steam
velocity against nozzle and false readings result.]

Fig. 19 indicates certain locations of sampling nozzles from which
erroneous results will be obtained, the reasons being obvious from a
study of the cuts.

Before taking any calorimeter reading, steam should be allowed to flow
through the ins