AMPLIFICATION OF THE LAW OF POISEVILLE

37

Tube
Radius, inches
Length, inches

Narrow ,
0.053844
18.092

Mean. . .
0.077394
41.650

Wide ...............
11.391400
39.858

FIG. 8.—Apparatus of Reynolds for studying the critical regime.
Inspection of the figure shows that with the lowest pressure and
the smaller tubes the efflux is a linear function of the temperature
except at the highest temperatures. With the wide tube, however,
there is a maximum of efflux at about 37° even at the smallest
pressure. As the pressure is increased the maximum appears at a