212 



The curves plotted in fig. 5 show the relationship between the percentage yields 

 of the present provisional method, of the impractical prolonged washing method, and 

 of the proposed modified Allen-Marquardt method. Only the figures obtained in 

 testing the portion of the Allen-Marquardt method which follows the beginning of the 

 oxidation process are represented. 



3 /OS 



\ 





O./SO 



0.3SO 



0.400 



FIG. 5. Comparison of three methods for the determination of amyl alcohol. 



The curve shows that uniform results can not be obtained by the present provisional 

 method, and that if the washing and distillation method, an impractical procedure, 

 be adopted, high yields will probably only be obtained on the low-content samples. 

 The curve developed by the runs on varying amounts of amyl alcohol by the pro- 

 posed modification of the Allen-Marquardt method gives a higher and more uniform 

 yield for all amounts and one which approximates closely to 100 per cent. The work 

 of developing this latter curve represents 62 runs on varying amounts of amyl alcohol 

 from 0.05 to 0.53 gram, and the manipulation of three analysts. 



The fact of obtaining a higher and more uniform yield caused us to prepare and send 

 out to 18 collaborators, 11 of whom reported, the samples described in the report of the 

 associate referee on distilled spirits for this year (see p. 25). The comparison of the 

 old and the modified method and the results of the collaborative work are there pre- 

 sented by the table and curves, and distinctly show the advantages of the proposed 

 modified method. 



