BY FRANK SMITH. B.SC, F.I.C., AND L. A. MESTON. 17 



The Liquid Fatty Acids were found to have a mean 

 molecular Aveight of 277.0. The iodine value is 84.0. We 

 conclude that the unsaturated acid of Queensland nut 

 oil is wholly oleic acid. 



The mean molecular weight and iodine value obtained 

 are, however, considerably loA\'er than the value for pure 

 oleic acid (282 and 90). an indication of the presence of a 

 saturated acid of lower molecular weight.* 



The Solid Fatty Acids were obtained as a white 

 cake melting at 54° C. They were found to have a mean 

 molecular weight of 273.0 Fractional crystallisation 



from alcohol gave in order of solubility fractions melting 

 as under. 



(1) 50"' C.-o5° C, a mixture, containing also proportion of iin.sat- 



urated acid 



(2) 56° C. -58° C, (irincipallv palmitic acid. 



(3) 62° C pure palmitic acid. 



(4) 69.5" C. pure stearic acid. 



From the lithium salts prepared from the fraction of 

 loAvest melting point was obtained by a])propriate treat- 

 ment of alcohol a small portion of salt yielding on 

 decomposition with mineral acid, crystalline acid melting 

 at 51° C. The melting point of myristic acid (Mol. Wt. 

 228) is 53° C. Myristic acid is probabh' present and may 

 also occur in some quantity in the liquid fatty acids prepared 

 by the lead-salt -ether process. 



Summary. 



(1) The nut of Macadamia ternifolia comj)ares favour- 

 ably in composition with that of edible nuts, such as the 

 almond. 



(2) It contains 66 per cent, of an edible non-dr\'ing 

 oil of low iodine value, and comparatively high content of 

 glyceride of saturated fatty acids. 



(3) The oil is composed of glyceride.s of oleic, palmitic 

 and stearic acids, with some proportion of glyceride of myristic 

 acid. 



We desire to acknowledge our indebtedness to the 

 chiefs of the Government Laboratories, Brisbane, for 

 facilities for the carrying out the present and preceding 

 investigation on the composition of prickly -pear seed oil. 



* The lead-salt-ether method does not affect the absolute separation 

 of unsaturated and saturated acid. 



