effects of radium rays in the soil i39 



Experiment 36 

 April 15, II : 15 A. M. 



Twenty unsoaked seeds of *' Lincoln " oats were sown in soil in a 

 6-inch pot, and a rod coated with a *' Lieber's radium coating" 

 (10,000 X ) was thrust vertically into the soil in the center of the pot. 

 All the seeds were placed with the radicle vertical, and the embryo- 

 side of the seed facing the radium-coated rod. 



Control with no rod, and both cultures placed in a glass frame in 

 the propagating house. 



April 28, 5 P. M. 



Heights of the seedlings from soil-surface to tips of second leaf : 



Radium Control 



77.00 mm. 113.00 mm. 



91.50 86.50 



94.50 ' 107.50 



83.50 ■ 90.00 



64.00 0.00 injured 



21.50 39.00 



61.00 20.00 



107.00 32.00 



44.50 109.00 



116.50 63.00 



0.00 injured 94.00 



91.00 37'00 



98.50 67.00 



44.00 0.00 



71.50 93.00 



69.00 170.00 



24.00 160.00 



78.00 148.00 



79.00 67.00 



0.00 injured 108.00 



1,316.00 mm. 1,604.00 mm. 



Average of 18, 73.11 + mm. Average of 19, 84.42 -f- mm. 



April 29. 



Cultures photographed (figure 26), and experiment closed. 



May 12, 5 P. M. Experiment 37 



Into each of three 6-inch pots were planted eight unsoaked 

 seeds of the bean [Phaseolits). Into the center of the first pot (R) 



