— — 
According to Smith the oil of Eucalyptus hemiphloia contains an 
aldehyde Qo^id^' aromadendral, which boils at 210^ with decom- 
position, and which has an odour reminding of cuminic aldehyde. 
The aldehyde forms an oxime melting at 84^, and a phenyl hydrazone 
of the melting point 105°. When oxidised with alkaline permanganate 
solution it yields as oxidation products an acid of the melting point 
259°- — ^260°, and cineol(?). Chromic acid mixture oxidises it to the 
acid ii^elting at 110°. 
This result differs from that obtained by us on a previous oc- 
casion 1) with an oil of Eucalyptus odorata, according . to which the 
aldehyde having an odour like cuminic aldehyde, when oxidised with 
permanganate, yields cuminic acid. Smith's work now has induced 
us to study this body once more in an Australian oil whose source 
could not be discovered but whose odour was exactly like that of 
Eucalyptus odorata. When extracting about 1,000 kilos oil with solu- 
tion of sodium bisulphite, we obtained about 2,5 kilos aldehyde which 
possessed a strong odour reminding of cuminic aldehyde. In order 
to remove from this product the slight non-aldehydic admixture, 
600 grams of the aldehyde fraction were again converted into the 
bisulphite compound. As the latter, on account of its slimy con- 
stituency, could only be purified with difficulty by means of alcohol 
and ether, we dissolved it in water and thus obtained by repeated 
extraction with ether a complete purification. The aldehyde liberated 
from this solution and driven over with steam distilled between 
50° (17 mm pressure) and 85° (5 mm pressure), and of this about 
470 grams at 80,5*^ to 85^ (5 mm pressure). This portion was al- 
most colourless, and had the exact odour of cuminic aldehyde. A 
fraction passing over at 82,5° to 84° (5 mm pressure), had the fol- 
lowing physical constants: d^go = 0,9828; = + 0°; boiling point 
228° — 238°. It had the quite remarkable property of oxidising in 
a short time when exposed to the air. In a solution of acetic acid 
the aldehyde formed a semicarbazone whose melting point, precisely 
as with cuminic aldehyde, lay between 202° and 207°, according to 
the manner of heating. The phenyl hydrazone recrystallised from 
ligroin showed the melting point 126^ — 127^. The oxime melted at 
58°. On oxidation with permanganate there was formed from the 
aldehyde an acid of the melting point 116° — 117'^. A mixture of 
cuminic acid with this acid had the same melting point. According 
to these results there appears to be no doubt whatever that the alde- 
hyde was cuminic aldehyde. 
We then submitted the portions of the oil, boiling below 80° 
(about 120 to 125 grams) to a further examination. They consisted 
1) Report April 1889, 19. 
