EXPERIMENTAL WORK ON FLOW OF STEAM. 141
6. The velocity attained depends to some extent upon the
rounding of the orifice or entrance to the nozzle, and may be
greater with the square or slightly rounded entrance than
when the rounding is of greater radius.
7. As shown in Figs. 53 and 54, from the experiments
of Messrs. Weber and Law in Sibley College, and Fig. 55,
Apparatus used in Sibley College experiments with nozzles and buckets.
from Dr. Stodola's "Steam-turbines," there is, with all shapes
of orifice there represented, a sudden drop of pressure immune-
diately in the narrowest section of the orifice, to below the
back pressure, then a rise of pressure as the steam leaves
the orifice, accompanied by variations above and below the
back pressure, till the pressure in the jet gradually steadies.
down to that of the medium into which it is flowing. The
Sibley College experiments were made with the searching-tube
