LECTURE IX.] HISTORY OF CHEMISTRY. iyi 



radicals may be carried out. Highly complicated formulae are 

 thus obtained, of which I can only instance a few : 



Malaguti's chlorinated ether : 



C 4 H O 3 + 2 C 4 H 6 C1 6 . 53 



Malaguti's chlorosulphuretted ether : 



(C 4 H 6 3 + 2C 4 H 6 C1 6 ) + (C 4 H 6 3 + 2QHA) etc. 54 



His conception of chloracetic acid is very important as we 

 shall find further on ; he regards it as a compound of oxalic 

 acid with chloride of carbon : 



C 2 C1 3 + C 2 3 



whilst acetic acid remains as the trioxide of the radical acetyl, 

 C 4 H 6 or C 4 H : ,. Even in 1840 he still contests the similarity in 

 the constitution of the two compounds, and does not permit 

 himself to be shaken in this by their analogous behaviour with 

 potassium hydroxide. 55 



This view was not long tenable, however, in face of the 

 constantly increasing number of substitution products, very 

 many of which exhibited unmistakable analogies with the 

 original substances. When Melsens succeeded, in 1842, in 

 reconverting chloracetic acid into acetic acid, by treatment with 

 potassium amalgam, 50 and thus proved that chlorine can be 

 replaced by hydrogen again so that the original substance is 

 reproduced, even Berzelius was compelled to make an admis- 

 sion. He says : r> ~ " If we recall to memory the decomposi- 

 tion of acetic acid by means of chlorine with formation of 

 Chlorkohlenoxahdure (chloracetic acid), another view as to 

 the composition of acetic acid presents itself as possible. In 

 accordance with this view it would be a coupled 5S oxalic 

 acid whose copula is C 2 H ; >, as the copula of the Chlorkohlen- 

 oxalsciiire is C 2 C1 3 ; consequently the action of chlorine upon 

 acetic acid would consist in the conversion of the copula 

 C 2 H 3 into C,C1,." 



53 Berzelius, Jahresbericht 1840, 375 ; here also Berzelius still writes 

 H instead of H._,. 54 Annalen. 31, 113 ; 32, 72. 5r> Ibid. 36, 233. 



5(i Ann. Chim. [3] 10, 233. 57 Lehrbuch. Fifth Edition, I, 460 and 709. 

 r>8 Berzelius here employs a word that had been introduced into the science 

 by Gerhard t. 



