i8o Journal of Agricultural Research voi. xvi.no. ? 



work, that is the digestion was carried on in a very faintly acid solution, 

 the acidity being due to the acids present in the sorghum. If this 

 assumption is made, the results in experiments 6a and 6b seem to show 

 that no nonglucosidic hydrocyanic acid exists in the sorghum. Of 

 course it is possible that the nonglucosidic acid was distilled over in the 

 first ICO cc, but this would not be in harmony \vith Willaman's suppo- 

 sition that it is the hydrocyanic acid that is obtained in 5 per cent of 

 tartaric distillation that causes the poisonous effect and which is a non- 

 glucosidic acid. Furthermore, the fact that no acid was found in the 

 distillate from sample 3 when it was ground under 5 per cent of tartaric 

 acid and distilled from the acid solution shows that nonglucosidic acid 

 is not present. 



The results in experiments 9a and 9b show that when a dry sorghum 

 is digested with 5 per cent of tartaric acid a considerable percentage of 

 the hydrocyanic acid is not liberated, and when this is taken in con- 

 nection with experiment 9c, one may conclude that the water was ab- 

 sorbed by the dry substance more rapidly than was the acid and that 

 some hydrocyanic acid was set free before the acid came in contact with 

 the glucosid. 



It is seen from the acid concentrations as found in experiments 7a and 

 7b that the contents of the paunch would be faintly acid in reaction when 

 the green or the dry sorghum is eaten. It might be argued that the acidity 

 would be neutralized by the alkalinity of the saliva ; but when the acidity 

 as found here is compared with the alkalinity of the saliva it is seen that, 

 when the alkalinity of the saliva is taken into account, and assuming a 

 normal saliva flow, the contents of the paunch w^ould still be slightly acid, 

 a condition most favorable for enzym action. This acid condition would 

 exist until rumination talkes place, when the acid would be neutralized. 



A comparison of the results of experiment loa and lob with that of 

 experiment i shows that all the hydrocyanic acid is liberated within the 

 first 15 minutes of the digestion. 



Willaman and West (ri) and other investigators have shown that 

 hydrocyanic acid gradually disappears from sorghum during its growth, 

 so that but Httle is present in the mature plant. It was thought that this 

 might not be true if large am^ounts of the acid had been formed as a 

 consequence of dry weather, in the sorghum at some stage of growth. 

 Sample 4 had been stunted by dry weather, but it is seen from experiment 

 8 that nearly all of the hydrocyanic acid had disappeared. The per- 

 centage of hydrocyanic acid found in this sample should be compared 

 with that of sample i , which was doubtless greater still before the sample 

 was dried. 



No discussion is needed of the experiments 11 to 13b, inclusive. The 

 reason for making experiment 13c, v^^as that it was thought that possibly 

 as shown in my work, the enzym is rendered practically inactive by dilute 

 alkaline solution, and it might be that the hydrocyanic acid would not 



