UTILISATION OF RESIDUES OF ESSENTIAL OIL. 219 
THE KCONOMIC UTILISATION oF THE RESIDUKS 
FROM THE STEAM RECTIFICATION orf THE ESSEN- 
TIAL OIL or EUCALYPTUS CNEORIFOLIA anpb 
THE GERMICIDAL VALUES OF THE CRUDE OIL AND THE 
PURE ‘ ACTIVE’ CONSTITUENTS. 
By A. R. PENFOLD, F.C.S., 
Economic Chemist, Technological Museum, Sydney. 
and 
R. GRANT, F.C.S., 
Assistant Microbiologist, Department Public Health, Sydney. 
* [Read before the Royal Society of N.S. Wales, December 6, 1922. ] 
In Kangaroo Island, South Australia, large quantities of a 
narrow leaf Mallee, Hucalyptus cneorifolia, are distilled 
annually for its essential oil. It is the principal tree on 
the island from which eucalyptus oil for pharmaceutical 
use is obtained, and being of a rich reddish-brown colour 
with a most pronounced odour of the aromatic aldehydes 
requires rectification by steam distillation. This procedure 
results in the accumulation of fair quantities of a dark 
coloured residue, which is usually run to waste, and for 
which a use is desired. 
On this account Mr, J. N. Hardwicke of the island men- 
tioned, kindly furnished us with a gallon sample, and our 
results show that this waste product contains very valu- 
able constituents that can be utilised commercially. The 
almost black, though mobile oil, was found to contain over 
6% phenol (australol), and 257% aromatic aldehydes (prin- 
cipally cryptal), the remainder being sesquiterpenes, 
alcoholic bodies and polymerised constituents, as well as 
colloidal iron compounds derived from the stills. At 
