, M. Buff on some Compounds of Ethylene. 375 



These acid-forming radicals contain, in addition to carbon and hy- 

 drogen, oxygen and other elements belonging to the oxygen group. 

 They are closely connected with the radicals of the alcohols, and 

 this close connexion is particularly well established between the first 

 series of alcohol-forming radicals and the corresponding series of acid- 

 forming radicals. 



Methyle, C^ H3-2H:+20=Formyle, C^HOg 

 Ethvle, C4 H3-2H + 20=Acetyle, C H3 0„ 

 Propyle, Cg H7 - 2H -h 20 = Propionyle, Cg H^ O^. 



Formic, acetic and propionic acids are formed by the imperfect 

 oxidation of methyle-, ethyle- and propyle-alcohol, and we may con- 

 sider them to be simple substitution-products of these alcohols. 



By means of the electric current we are able to produce ethyle, 

 methyle and hydrogen from propionic, acetic and formic acids, and 

 these acids we may reproduce again by the action of hydrate of 

 potassa on the cyanogen compounds of hydrogen, methyle and 

 ethyle. 



Both series of radicals are chained together by these reactions, and 

 we may view acetyle and propionyle as formyle, the hydrogen of 

 which is replaced by methyle and ethyle. 



Formyle =C^ (H) O^ 



Acetyle =C^lc^B.^)0^ 



Propionyle =0^ (C4 H^) O^. 



There is no doubt that the same relation exists between the hydro- 

 carbons of the other series of radicals and the radicals of the corre- 

 8|>onding acids, between allyle, C^ H5, and the radical of acrylic acid, 

 acryle Cg Hj Oj, and between methylene, Cj Hg, ethylene, C4 H^, pro- 

 pylene, &c., and the radicals of the bibasic acids, which are homo- 

 logues of succinic acid, Cg Hg Og. 



The biatomic radicals are in general far less studied than the 

 monatomic radicals ; still they occur iu many compounds, and are 

 met with in different departments of chemistry. 



In addition to the terms already mentioned, we find them in the 

 phenyle, benzyle, naphthyle and other series. 



In the hope of adding some facts to the history of the polyatomic 

 radicals, I have made some experiments with chloride of ethylene, 

 C^H.CU. 



This compound, as well as the bromide of ethylene, refused to act 

 in many instances ; in others it underwent the same change which is 

 induced by the action on it of a solution of potassa in alcohol, split- 

 ting into the compound C4 H3 CI and hydrochloric acid. 



On boiling chloride or bromide of ethylene with an alcoholic so- 

 lution of suli)hocyanide of potassium, a very definite reaction takes 

 place. The change being completed, the alcohol is separated by 

 distillation, and the residue treated with a small quantity of cold 

 water in order to remove chloride or bromide of potassium, which is 

 produced, and the excess of sulphocyauide of potassium. The more 

 or less coloured residue is then dissolved in boiling alcohol, and the 



