A portion of the Trials lifted for inspection. 

 The Experiments in 1915 were divided into two main series. 



SERIES 1. TRIALS WITH TOMATOES, POTATOES, 

 RADISHES, and LETTUCES. 



All the plants were grown in ten-inch pots, the total number of pots being 

 736. Each of the four subj ects was grown in 



(a) Silver sand. 



(b) Unmanured soil sterilised at 200 Fahr. 



(c) Sterilised soil to which Farmyard Manure had been added. 



The three sets were each dressed with various radio-active materials, 

 as nearly as possible at a ratio of i/4,oooth of a milligramme of Radium Bromide 

 per pot, thoroughly incorporated with the sand or soil. All the pots were 

 sunk into the ground. Plain tap water was given, as required, and in other 

 respects the whole of the plants of each subject received equal treatment. 



Suitable " Controls " were arranged in duplicate, one set being placed 

 at each end of the various sections. 



Detailed tables, together with notes on the trials, are given on pages 8 to 13. 



SERIES 2. TRIALS WITH VEGETABLE MARROWS, 

 CARROTS, ONIONS, and SPINACH BEETS. 



In this series the plants were grown in open-ground plots, to which no 

 manure had been applied for some years previously, the total area being 

 216 square yards. Each plot, containing 18 square yards (about ^^th of an 

 acre), was divided into four equal sections, and sown in due course with seeds 

 of the four subjects named above. 



The various radio-active materials, each applied in an approximately equal 

 degree of strength, were lightly forked into the top three inches of soil. In 

 addition, a dressing of Complete Fertiliser was given to one half of the section 

 devoted to each subject. Radium was therefore tested on plants growing 

 (a) in unmanured soil, and (b) in soil to which a Complete Fertiliser had been 

 added. For comparative purposes, " Control " plots were also sown. 



Detailed tables, together with notes on the trials, are given on pp. 14 to 17. 



In addition to the foregoing, sundry experiments were made with Mustard 

 and Antirrhinums grown in double pots, and also to test the action of Radium 

 on the germination of Rape seed. See pages 18 and 19. 



