198 F. B. GUTHRIE AND R. HELMS. 



r With the exception of 32, none of the seed in the above 

 pots germinated. In No. 32 the seed had germinated, but 

 the plants were very feeble and were all dead when 

 examined on July 1st. 



The pots were therefore resown on July 3rd with soil 

 No. 2, the following quantities of sodium chlorate being 



added : — 



Pot 32, *001 per cent. Na010 3 

 „ 33, '003 „ 



„ 34, '005 

 „ 35, -01 



In Pot No. 35 the seed germinated as with pot 32 in the 

 preceding experiment, but the plants were very feeble, 

 and by July 24th they were all dead. 



Pot 34, the seed germinated but growth was feeble, and 

 plants were dying when examined on July 24th and 

 died subsequently, being all dead by August 26th. 



Pot 33, seed germinated but plants were growing very 

 feebly on July 24th and August 26 th. 



Pot 32, the seeds germinated well, the plants on July 24th 

 were weak and slightly discoloured. By August 26th 

 they had recovered and were growing fairly. 



The conclusions drawn are the following : — Germination 

 is not seriously affected until the amount of sodium chlorate 

 in the soil approaches *01 per cent., but the subsequent 

 growth of the plant is injuriously affected by so small an 

 amount as '001 per cent, and the limit is exceeded at *003 

 at and above which quantity the presence of sodium 

 chlorate is fatal. 



Experiments ivith arsenious acid. 

 Since the recent enquiry in England into the cause of 

 wholesale poisoning by beer, which revealed the fact that 

 the glucose used in brewing frequently contained arsenic 

 traceable to the pyrites and sulphur used in the manufac- 

 ture of sulphuric acid, attention has been directed towards 



