§ 18. MELTING POINTS OF FAT ACIDS. 17 



Heintz also n6ticed that a mixture of three fat-acids could melt 

 at a still Idwer temperature, even if the third fat-acid added 

 possessed a higher melting-point than either of the others. A 

 mixture of 30 parts of palmitic and 70 of myristic acid melts at 

 46-2°, and tolidifies amorphous. To 20 parts of this mixture 

 stearic acid was added in the following proportions, and melting- 

 point and manner of solidification observed : 



To 20 parts of a mixture of 30 parts of myristic with 70 of lauric 

 acid, melting at 35-1° palmitic acid was added, and the following 

 observations made 



Manner of Splidiiication. 

 Amorphous. 



Indistinct minute needles. 

 Minute needles. 



These tables show clearly that it is important to examme the 

 EraCtions in the succession Ln which they were prepared. For 

 instance, supposing the first piecipitate to have yielded a fat- 

 acid inciting at 68", which might consequently be cODsidered as 

 stearic acid, the following precipitates fat-aoids melting at about 



2 



