37G T. HAGA 



équation.* This fact makes greater the need ah'eaJy present of 

 assuming that the hydroxyamine in decomposing must yield a very 

 little deoxidised nitrogen, either in the free state or in union with 

 iodine. Evidence of the correctness of this assumption seems to be 

 afforded by a remarkable phenomenon to be observed in titrating 

 hydroxyamine v\dth iodine. A very weak solution being mixed with 

 very little sodium bicarbonate, insufficient for the complete titration 

 by iodine, the solution of the latter is added just beyond the point 

 when it is no lorjger bleached. If now to this solution a little more 

 sodium bicarbonate is added, a milkiness soon appears, strikingly 

 resembling that of iodoform appearing under similar conditions when 

 in place of hydroxyamine a trace of alcohol is present. It disappears 

 on adding more iodine, but may be reproduced several times in 

 succession before the hydroxyamine is exhausted. The substance 

 causing this turbidity may perhaps be in reality an iodamine, related 

 to nitrogen as iodoform is related to carbon. 



I am much indebted to Dr. Divers for suggestions in carrying 

 out this investigation. 



* The solutiou jifter titration always yields a little fiee iodine wlieu acidified, and this in 

 absence of any iodate in the potassium iodide used, is one proof of the presence of nitrite. 

 The solution also, when freed first fiom all iodide, and then tested with acidified ferrous 

 sulphate, always gives the browu colour caused by a nitrite. 



