EUCALYPTUS AUSTRALIANA AND ITS ESSENTIAL OIL. 525 



Third Hour Oil. 



This sample was also forwarded by Mr. Gough. It shows 

 but slight chemical differences from the oil of the second 

 hour, except that the alcohol is a little more pronounced. 

 It had specific gravity at 15° == 0*9266; rotation a B + 2*6°; 

 refractive index = 1*4747, and was soluble in 1*1 volumes 

 70% alcohol. Addition of more alcohol determined the 

 presence of paraffin in both the second and third hour oils. 

 The saponification number for the ester plus that of the 

 free acid was 9*7; while with the acetylated oil it was 

 116*03. 



On distillation 55% came over below 193°, and 35% 

 between 193° and 225°. 26% of cineol was found to be 

 present iu the first fraction. The specific gravity of the 

 first fraction was 0'9145; and the refractive index =1*4669. 

 The second fraction had specific gravity 0*9267; rotation 

 ■a D — 1*4; refractive index — 1*4770. The saponification 

 number for the ester plus that of the free acid was 9.4. A 

 portion of the second fraction of the third hour oil was 

 acetylated, when the saponification number had increased 

 to 124*5. This indicates an ester percentage of 43*6 if the 

 alcohol has the Oi H 17 OH molecule. 



The determination of this alcohol is reserved for a later 

 communication. 



