case the area under the curve between the values r & cr and r s - cr 

 divided by the total area under the curve is o 68. If g(r) de- 

 notes the curve faired through the measured points, this entailed 

 measuring the areas f r g(s)ds for enough values of r to plot a 



curve, which will be denoted by 2G(r) e A value <r was then 

 determined from G(<r ) s 0„68G(o©) o This will not, of course, be 

 the true value of a B The true value, denoted by <£Ti, was then 

 determined by the method described in the appendiXo Two methods 

 for determining A are described in the appendix,, Tests with two 

 different curves gave nearly the same value for A for each method 

 so that it was decided to use the second method which involved 

 somewhat less labor The results of this analysis are shown in 

 the following table,. The meanings of the letters X, L, and M are 

 shown in Figure 1„ 



inches inches inches 



inches 



o 017 

 0o027 

 o 040 

 0,052 



0o022 

 0.037 

 0o050 



1. 30x10=3 

 1. 42xl0™3 

 2 22x10=3 



22 



X @v Gi 



inches inches inches 



0o50 0o023 0*016 



0o7^ o 030 0„025 



l o 00 Oo036 032 



sdo inches 

 0„ 84x10=3 

 lo 21xlO"3 

 I. 46x10-3 



lo 38x10-3 



The values of flr^ and A are omitted for the station L/M m 15 ? 

 X s 0„75 in because a corrected value of cr did not seem to 

 existo This would seem to indicate that the measured value of 

 & a 0o017 in» was impossible,, at least under the assumption that 

 the effective value of the sampler diameter was 060 in„ Dis- 

 crepancies of this sort could probably be avoided in a more care- 

 fully controlled experiment in which the rate of removal of 

 fluid through the sampler was adjusted to be equal to or less 

 than the free-stream velocity 



Since the total amount of dye passing in unit time each 

 station downstream of the injector should be the same, one will 

 expect A to be a constant.. The constancy of A provides a sort 

 of check upon the accuracy of the experiments, providing, of 

 course, that the rate of dye release has been kept constant dur- 

 ing all the measurement So Inspection of the values of A in the 

 table above shows that the variation is not large with the ex- 

 ception of two points 1 the value of A for L/M s 15 and X « 1„50 

 in e is too large by almost a factor of 2, whereas the value for 

 L/M m 22 and X s 0,50 in„ is too small by a substantial amount. 

 This discrepancy may have arisen from the general crudeness of 

 the experiments or perhaps was caused by an actual error „ 



The transverse intensity of turbulence may now be com- 

 puted from the values of cr « Let X be the distance measured 

 downstream from the end of the dye injector and 3e t Y be 

 distance measured vertically.. If a particle starts at the 



