i86 



MISCELLANEOUS EXPERIMENTS 



This experiment was thrice repeated, with results the same in 

 kind as those above. 



Experiment 66 



Object : To ascertain the effect of the rays from a Welsbach gas 

 mantle buried in the soil on the germination and growth of timothy 

 grass seeds planted in the same soil. 



In a flower pot of earth was buried vertically the Welsbach 

 mantle, style " Yusia," No. 189, purchased in the market, and on the 

 surface of the soil were sown seeds of timothy grass. Control cul- 



FiG. 47. Experiment 65. Effect of Thorium Rajs from a Welsbach Gas Mantle on 

 the growth of Timothy Grass. Cf. Fig. 46. 



ture with no mantle, and both cultures placed in the dark room, and 

 watered from below until the water had soaked up to the surface of 

 the soil. 



The seeds germinated in both cultures and produced good 

 healthy plants, but throughout the duration of the experiment no 

 difference could be detected in the height or other characters of the 

 plants in the two pots. 



The experiment was repeated, but with similar, /. e., negative, 

 results. 



Summary 



The results of the preceding experiments, covering a wide sys- 

 tematic range of plants, are in conformity with those previously de- 

 scribed. Rays from radium bromide of 7,000 x apparently acceler- 

 ate the germination of pollen grains of Ascle-pias curassavica under 

 the conditions imposed, while cell-division of commercial yeast was 



