352 Journal of Agricultural Research voi. xviii. No. 7 



SERIES 8 



To determine the relation of some other salts to the sodium-chlorid 

 tolerance the following set was started on March 30 : 



SOLUTION NO. CONCENTRATION OP SOLUTION. 



1 Distilled water. 



2 4,000 parts per million of sodium chlorid + 30 parts per million of calcium 



sulphate. 



3 4,000 parts per million of sodium chlorid + 30 parts per million of calcium 



oxid. 



4 4,000 parts per million of sodium chlorid + 30 parts per million of magne- 



sium sulphate. 



5 4,000 parts per million of sodium chlorid + 30 parts per million of barium 



chlorid. 



6 4,000 parts per million of sodium chlorid + 30 parts per million of potassium 



chlorid. 



7 4,000 parts per million of sodium chlorid + 30 parts per million of sodium 



nitrate. 



8 4,000 parts per million of sodium chlorid + 30 parts per million of sodium 



phosphate. 



9 4,000 parts per million of sodium chlorid + 30 parts per million of ferric 



chlorid. 

 10 4,000 parts per million of sodium chlorid + 30 parts per million of potas- 

 sium alum. 



At the end of seven days the plants were photographed (PI. 44). In 

 this experiment the calcium oxid produced the best plants and calcium 

 sulphate the next best. While the effect of the barium chlorid and mag- 

 nesium sulphate was not marked, it was evident that they exerted some 

 action upon the sodium chlorid, while the potassium chlorid, sodium 

 nitrate, sodium phosphate, ferric chlorid, and alum produced little or no 

 change. 



On March 30 two pots of sand were started. No. i was watered with 

 4,000 parts per million sodium-chlorid solution and the other with the 

 same solution to which had been added 30 parts per million of calcium 

 sulphate. The plants were grown for 1 6 days and then photographed 

 (PI. 45, A). The beneficial effect of such a minute amount of lime in 

 sand cultures is clearly shown in this experiment. 



SERIES 9 



In Plate 45, B, are shown 3 -day-old plants grown in the following solu- 

 tions of sodium sulphate : 



SOLUTION NO. CONCENTRATION OP SOLUTION. 



1 4,000 parts per million of sodium sulphate. 



2 4,000 parts per million of sodium sulphate -f 30 parts per million of cal- 



cium sulphate. 



3 4,000 parts per million of sodium sulphate + 30 parts per million of cal- 



cium oxid. 



4 4,000 parts per million of sodium sulphate + 30 parts per million of mag- 



nesium sulphate 



5 4,000 parts per million of sodium sulphate + 30 parts per million of barium 



chlorid. 



