is SUNDRY EXPERIMENTS. 



TRIALS WITH MUSTARD AND ANTIRRHINUMS 

 GROWN IN SINGLE AND DOUBLE POTS. 



The object of these trials was to ascertain the effect of Radium on plant 

 life when the radio-active Ores were npt brought into actual contact with the 

 roots. The means adopted was to place a lo-inch pot' containing plants 

 into a pot of the 12-inch size, and to fill in the intervening space with radio- 

 active Ore of about the same degree of strength as used in the experiments 

 already described. For comparison, plants of. each subject were grown in 

 single pots containing (a) plain soil, (b) soil and Complete Fertiliser, (c) soil 

 and radio-active Ores, (d) soil, Complete Fertiliser, and radio-active Ores. 

 Where the double pots were used, the subjects were planted in (a) plain soil, 

 and (b) soil and Complete Fertiliser. 



a.l.po.. 



Experiments with Mustard. 



, 

 Plain sol Dressed with R^d "m Comlete Complete Complete Fertiliser. 



- JS&tt SSSS. *g!- H.,:,,. 



TRIAL NOTES ON MUSTARD. Seed sown September i. 



The first signs of germination were visible on September 6 in the single 

 pots dressed with Radium (one of which contained a proportion of Pure Radium 

 Bromide), and in the double pots where Complete Fertiliser had been 

 incorporated with the soil. The double pots with Radium between, and filled 

 with plain soil, were a day later in germinating. 



By September 10 the most forward plants were found in the double 

 pots dressed with Complete Fertiliser. Next in order came those in the single 

 pots containing a proportion of both Radium and Complete Fertiliser. 



On September 15 the plants growing in plain soil in single pots had 

 improved and were stronger than those treated with Radium (unmanured), 

 whether mixed with the soil or placed between pots. The trials in double 

 pots (unmanured) showed greater strength than those in the unmanured single 

 pots containing Radium. But the strongest of all were in the single pots 

 dressed with Complete Fertiliser only. 



TRIAL NOTES ON ANTIRRHINUMS. 



The plants were potted on June 14, and by the end of July those which 

 had received a dressing of Complete Fertiliser were decidedly superior to the 

 others. In no instance was any advantage from the use of Radium observed, 

 whether the material was incorporated with the soil or placed between pots. 

 At the end of September the condition of the plants was relatively the same. 



NOTES ON THE GERMINATION OF MUSTARD SEED. In the 1914 

 experiments it was found that the germination of Rape seed was accelerated 

 by dressings of radio-active Ore, and that a light dressing was apparently 

 as effective as a heavier one. There was, of course, the possibility that germina- 

 tion might have been influenced by chemicals other than the Radium contained 

 in the various Ores. But it is interesting to note that in some tests made 

 in 1915 with Mustard, the seeds sown in pots dressed with Pure Radium 

 Bromide were among the first to start into growth, which apparently shows 

 that accelerated germination is due to Radium and not to impurities in the 

 Ores. The influence of the Radium on the Mustard plants, however, was not 

 maintained beyond the development of the second leaf. 



