271 



Transactions. 



This practically agrees with Eisenreich's experience. He obtained the 

 first four fractions melting at 83°. It seems strange that he did not 

 proceed with further fractional precipitation. 



Fractions 1 and 2 were each fractionally precipitated again, and it was 

 found that the regenerated acids from the first two precipitates had risen 

 3° in melting-point. 



Fractions which melted within 1° were mixed before the next precipi- 

 tation was proceeded with. After four consecutive precipitations of the 

 highest melting fraction in each case, there resulted an acid melting at 

 88-5°. This fraction was not altered in melting-point by a series of 

 further fractional precipitations, and must be regarded as pure melissic 

 acid, which, according to Brodie* and to Schwalb,f melts at 88-8!*°. Jt 

 is, however, to be noted that the melissic acid from the oxidation of 

 canaiiba wax is stated by MaskelyneJ to melt at 91°. 



The following is a scheme of precipitations employed in the isolation of 

 melissic acid. The melting-points given are those of the regenerated acids : — 



Fractional Precipitation of 50 Grams "Apparently''' Pure Montanic Acid (Melting-point, 82°). 



I 



I 



I, 83°-84 c 



II, 83°-84° IIT, 82° IV, SV V, 78°-80 L ' 



d 



S7°-88° 



I I I I I 



a b c 2a 2b 2c 



86°-87° 86°-87° 84°-85° 85-5°-86-5° 85°-86° 83°-84 J 



Mixed (a) Mixed (-26) Mixed (a) Mixed (26) 



86-5°-87-5° 



h % j 



88°-89° 88°-89° 86-5°-87° 



| Mixed (h) Mixed (/) 



/ 9 



86° 82° 

 Mixed III 



k I 



88-5° 8S°-89° 



Melissic acid 



m 



87°-88° 



n 



87°-8S° 

 Mixed (m) 



o 



86°-87° 



P 

 85-5° 



t u q r s 



88°-89 87-5° 87-5°-88-5° 86-5°-87-5° 85-5°-86-5° 

 Mixed (k) Mixed (?) Mixed (m) 

 Melissic acid 



Repeated fractional precipitation failed to yield an acid melting at about 



83° which could be considered pure, but from fraction 5 precipitation 



yielded lower fractions, which when repeatedly crystallized melted at 



* Phil. Trans. Roy. Soc, 1848. 



t Annalen, 235, p. 135. 



% Journ. Chem. Soc, 1869, vol. 22, p. 87 



