58 REPORT— 1869. 



We know, therefore, tlie radicals of adipic acid and their arrangement if we 

 possess the same knowledge with regard to iodopropionic acid. 



The above elegant synthesis has lately been performed by Professor Wislicenus 

 of Ziirich. M. JBerthelot has now succeeded in producing representatives of the 

 principal classes of hydrocarbons from the elements of carbon and hydrogen, and 

 Messrs. Bauer and Verson of Vienna have prepared from amylene, C^ Hj„, a 

 compound, C,o H,c, which appears to be identical with terebene, a body closely 

 allied to tm'peutine. 



Another way to determine the proximate constituents of molecules, is to take 

 the little structures to pieces, and to form a judgment of their constitution from 

 the radicals which thus can be extracted. This plan has been adopted by Mr. 

 Chapman, and described by him at one of our former Meetings. 



The more common and more reliable method for tlie determination of the 

 grouping of atoms in molecules is, however, the replacement of one or more of 

 them by atoms of another kind, and the careful examination of the properties of 

 the bodies thus formed. M. Gautier has recently obtained a new substance of 

 the same composition as acetonitrile, which he calls raethcarbylamine. According 

 to their formation, acetonitrile, as well as methcarbylamine, can be considered as 

 combinations of cyanogen and methyls CH3 ON. The two bodies, however, do 

 not possess the same properties ; if they are heated with potassic hydrate and 

 water, methcarbylamine produces formic acid and methylia, whereas the same re- 

 agents cause acetonitrile to form acetic acid and ammonia. Thus 



O2H3N + 2H,0 = CJIjO, + NH3 

 Acetonitrile. Water. Acetic acid. 



CHaN + 211,0 = CII.O, + NJ^j^^ 



Methcarbylamine. Formic acid. Methylia. 



In the first case, the radical methjd remains after the decomposition in union 

 with carbon, and in the second case in comljination with nitrogen. Accordingly 

 it is supposed that the same arrangement prevails in the undecomposed molecules, 

 and with this supposition all the other properties of methcarbylamine and aceto- 

 nitrile agree. In symbols these relations are expressed as follows : — 



iC" 

 r^ TT = methcarbylamine. 



■[ Co H3 = acetonitrile. 



This case of isomerism is most interesting, inasmuch as it furnishes a most in- 

 structive lesson on the grouping of atoms. The homologous bodies of uieth- 

 carbvlamine in the etliyl and propyl series have also been obtained. 



Isomerism, indeed, has received much attention during the last year, and a 

 great many interesting discoveries have resulted ; of these one more example 

 may be mentioned. We know two compounds of the formula ON, H4 0, the one 

 is amnionic cyanate, and the other urea. Until recentlj', only one corresponding 

 sulphur-compound, amnionic sulphocyanate, was known. Professor Reynolds has 

 succeeded in obtaining the true sulphur-urea, a body isomeric to amnionic sulpho- 

 cyanate. 



Thus every year produces results which improve our conceptions of the atomic 

 and molecular constitution of bodies ; and as our knowledge improves new questions 

 suggest themselves, and our power over the elements increases. It has already 

 become possible to prepare in the laboratory bodies of a very complex character, 

 such as a few years ago were only found in the bodies of animals or plants. 



Alizarin, the beautiful compound of the madder root, has been obtained by arti- 

 ficial means in the course of the j'ear by Messrs. Liebermann and Grrebe. Results 

 of such a nature render it highly probable that, at no distant period, it will be in 

 our power to prepare artificially nearly all, if not all, the substances found in 

 plants and animals. Here I must not be misunderstood. Organic structures, 

 such as muscidar fibre or the leaves of a tree, the science of chemistry is incapable 



