OF ARTS AND SCIENCES. 301 



The following comparison shows that the numbers obtained from 

 the analyses of the chloride correspond to those calculated for the 

 formula CgHgBrNoOgHCl (with the exception of the hydrogen,* which 

 w^as undoubtedly brought too high by the passing over of a part of 

 the halogen into the sulphuric acid bulbs). 



On the other hand, the numbers given by the analyses of the free base 

 indicate a substance containing one molecule less of water. 



The want of agreement between the percentages of hydrogen f is ex- 

 plained in the same way as in the analyses of the chloride. Other- 

 wise the numbers come as near as could be expected, when it is 

 remembered that the free base was so unstable that we did not dare 

 to purify it except by washing, and that it gradually turned brown 

 even when dry. 



In order to harmonize these results and determine the nature of 

 the substances we have found only three hypotheses. 



First, and most obvious. The two substances belong to different 

 classes, i. e. one is the chloride of the bromdiamidophenylacetic, acid 

 C^H.^BrNHgClNHoCHoCOOH ; the other is free bromamidooxindol, 

 CyHoBrNHofCHoCONH). 



If, on the other hand, the substances belong to the same class, — 



Second. They are the bromamidooxindol and its chloride. In this 

 case the chloride must contain one molecule of water of crystallization. 



Third. They are bromdiamidophenylacetic acid and its chloride. 

 In this case our analyses of the free base are incorrect. 



* The formula CgHuBrNoOoHCl requires 4.23 per cent of hydrogen, and is 

 therefore distinctly too high for Analysis II., and the analysis of the " chloride 

 of the free base " given later. The small amount of substance used in Analysis 

 I. makes the per cent of hydrogen in it of no value. 



t The formula CgHgBrNoO requires 3.93 per cent of hydrogen. 



