AND SCHONBEIN 93 



xyloidin as they have for some time done, especially 

 as they subsequently admitted the very obvious 

 difference between the two substances, and as I 

 prepared guncotton as early as last year. I had no 

 desire to assert my claims before the French Academy, 

 because I am convinced that impartial men of 

 science will come to a right conclusion on this 

 question. 



The last number of Poggendorff's Annalen contains 

 a few papers of mine, which may interest you inas- 

 much as they indicate the facts which led me to the 

 discovery of guncotton. The resinous substance 

 which is formed by the action of a mixture of nitric 

 and sulphuric acids on sugar appears to be a substance 

 quite analogous to guncotton, and if the latter is lignin 

 nitrate, the former must be nitrate of sugar. Possibly 

 the names nitrolignin, nitrosaccharine, nitroamylin, 

 etc. would be suitable for such compounds. Since 

 according to my view N0 5 does not exist, I con- 

 sider that the compound in question contains ]N"0 4 

 combined with an organic substance. The following 

 fact which I have ascertained appears to be of 

 especial interest, namely that flowers of sulphur 

 treated with a mixture of nitric and sulphuric acids 

 produce sulphurous acid even at low temperatures. 

 Why is sulphuric acid not formed under these circum- 

 stances ? I hold the unusual view that the sulphurous 

 acid formed under these circumstances is a secondary 

 product, derived from the change of hydrogen sulphide 

 to peroxide, in a manner analogous to the formation 

 of sulphurous acid by the action of water on chloride 



