14 
as those at the northern end, with the same regular gradation. 
Between the 50-pound and the 100-pound plots there is little 
difference, showing that 50 pounds produces about the maximu 
effect on — 
similar but ee relation. The t an in the apeepoutid 
plot are stunted by an excess of R / AF, just as was the spinach 
that occupied the same plot in the early spring. Now, the 
plants in the 1p Porae plot, lying across the pat th from the 200- 
next to the west, the celery plants show exactly the same series 
of differences as do the <r ips 
Had I performed no other experiments than these this year, 
I should have regarded the results as conclusive, since there is no 
other possible cause for the differences in the plants than the 
: A : : 
field the plots competed are acres in extent, so oe the radio- 
activity f avery nar pof ve other, 
and the diff i i uld show the f 
in activity of the radian: At Nutley on the other hand, no 
plot, even though no R A F was applied, was entirely free from 
radium influence, ee ee its yield above the normal, 
and decreased the differences between it and the radium-treated 
due to the uranium i areianiie in the R A F, because of the very 
small Except in part, this is obviously 
impossible, since the uranium ous: it paly. the plot in which 
it was placed. The only p f which 
could cross the path to the neighboring plot is the radium. 
All these results are permanently and indisputably recorded 
by a series of photographs, which display with great accuracy 
pnts differences between the Caper plo ts. 
In 
P ig table each | by the number 
