of a well-crystallised bisulphite compound separated out. When treated 
with a carbonate solution, these crystals developed the unmistakable 
odour of decylic aldehyde. Paucity of material prevented the direct 
demonstration of the presence of this body; in our opinion, this could 
only be successfully accomplished by working up very large quantities 
of oil. We would, however, point out that decylic aldehyde has been 
detected by us with certainty ^) as a constituent of oil of sweet orange, 
i. e. an oil which in its origin is closely allied to neroli oil. 
Phenyl acetic acid. Saponification of a portion of the fractions 
boiling at 82 to 97°, at 7 — 8 mm pressure, whose saponification 
number was 58, yielded an acid, which crystallised from water in 
well-defined small scales. In the pure state it melted at 76 to 77°, 
that is to say like phenyl acetic acid. The material was not in 
sufficient quantity to identify it further. 
Benzoic acid. A small quantity of this acid was obtained on 
saponifying the residue of the distillation. As it was strongly contaminated 
with resinified products and anthranilic acid, it was purified through 
the barium salt. The almost colourless product thus obtained melted 
at 116° to 117°, and, after subliming through filteiing paper, at 121^. 
When esterified with methyl alcohol and concentrated sulphuric acid, 
the unmistakable odour occurred of methyl benzoate. 
It may be accepted that phenylacetic and benzoic acids are not 
contained in the oil as such, but in the form of esters. In view of 
the high boiling point of the fractions in which they were detected, 
it is probable that they are combined with benzyl alcohol 2) or phenyl 
ethyl alcohol^). The latter could be detected, by oxidation into phenyl 
acetic acid, in a saponified fraction of the boiling point 210° to 220°. 
Alcohol Hjg O. With reference to this alcohol we would mention, 
that only after we had obtained a derivative of it in the examination 
of petitgrain oil, we examined the corresponding fractions of neroli oil 
for the same purpose. For this reason we confine ourselves in this 
instance to mentioning the fractions in which the alcohol was detected, 
together with their constants, and also an analysis of the phenyl urethane 
of this alcohol. 
Unsaponified as well as saponified fractions of the oil were employed 
for the detection. The fractions of the boiling points 76° to 78^, 
and 78,5° to 79°, at 7 to 8 mm pressure, which had an odour very 
similar to that of the corresponding fractions of petitgrain oil, were 
carefully distilled at ordinary pressure after repeated distillation in vacuo. 
The following fractions were isolated: 
^) Journ. f. prakt. Chem. II. 62 (1900), 524. 
^) Esters of benzyl alcohol have been repeatedly met with in essential oils. 
^) According to Hesse (Journ. f. prakt. Chem. II. 64 (1901), 259, phenyl acetic 
acid and phenyl ethyl alcohol are present in the oil of orange-flower water. 
