- 169 — 



M D 44,02. These results show that it is practically certain that camphene 

 P cannot be a saturated body with a tricyclic ring, because the excess of the 

 ascertained mean values of refraction over the values calculated for the 

 saturated formula Ci Hi 6 is not less than +2,12 and +2,14. It is true 

 that a tricyclic ring also effects a rise in refraction but not by far to such an 

 extent as indicated in these excess-values. From the observations on 

 cyclene, /^-bornylene and /?-pinolene, all of which are saturated tricyclic 

 compounds, it is clear that in a tricyclical system the tricyclic ring claims a 

 similar, and apparently only slightly larger increment than in other 

 cyclical bodies. From the spectrochemical observations which have been 

 made within the past few years it may be stated with certainty that cam- 

 phene cannot be a saturated compound. The examination of seven dif- 

 ferent camphene-preparations has shown the molecular refraction of cam- 

 phene to be larger than that calculated for the formula CioHie/^, and the 

 exaltations to equal EI^ + 0,32 and E2* D + 0,37. This behaviour points 

 to the semicyclic structure of camphene, and would appear to afford 

 spectrochemical proof of the corrections of Wagners camphene formula. 

 What has been stated above with regard to camphene is also applicable 

 to D-Z-fenchene and to its optical antipode, i-cZ-fenchene. Here, EI D = 

 + 0,33, a fact which can only be explained on the hypothesis of a semi- 

 cyclic double linking. Accordingly, the formula of ZM-fenchene would be 

 that given by Wallach and almost universally accepted. 



Wagner's Camphene-formula. 



D-Z-fenchene. 



G. G. Henderson and Miss M. M. J. Sutherland 1 ) have described as 

 camphylic acid an acid which they had obtained from camphene by 

 oxidising it with hydrogen peroxide. In a supplementary notice they 

 state 2 ) that Bredt has called their attention to the fact that Perkin had 

 also applied the name of camphylic acid to the acid obtained by him by 

 ^sing sulphocamphylic acid with alkalies. Moreover, Aschan informed 

 them that an acid apparently identical with camphylic acid had been 

 obtained by him by oxidising camphene with potassium permanganate at a 

 low temperature in acetic acid solution, and that he has suggested the name 



J ) Comp. Report October 1911, 134. 

 2 ) Proceed, chem. Soc. 27 (1911), 279. 



