12 
230° to 233°, which had the characteristic safrol-odour, was collected; 
it showed the specific gravity 1,10. The substance obtained in this 
manner crystallises without cooling it to — 25°; the melting point lies 
between 8° and 10°. It should, however, be mentioned, that the 
substance obtained after only one single distillation does not by any 
means possess the tendency of crystallising at a low temperature; on 
the other hand, the parts which have once crystallised appear to be 
readily capable of recrystallisation. 
In order to identify this substance with safrol, isosafrol was pre- 
pared by Eykman's method, and by oxidising the latter, piperonal of 
the melting point 37° was obtained. 
When the safrol was oxidised with potassium permanganate accord- 
ing to Tiemann, homopiperonylic acid melting at 127° to 128° 
was obtained. 
V. Detection of cineol. 
Fractions, I, II, and III were combined and distilled. The por- 
tions passing over at 174° to 179° were three times submitted to 
fractional distillation, when finally a fraction of 175° to 177° was ob- 
tained; specific gravity = 0,9024. 
A small quantity of this substance was placed on a watch-glass, and 
while gently heated some iodol added, when pretty crystals were ob- 
tained which, after re- crystallisation from alcohol, showed the melting 
point 120°. The body therefore represented the double-compound 
of cineol with iodol. In order to supply a further proof of the pres- 
ence of cineol, the hydrobromide compound of cineol was prepared, 
whose melting point lay at 53° to 54°. Although the melting point 
of cineol hydrobromide is given in literature as 56°, I believe that 
my substance was as a matter of fact, cineol hydrobromide. 
VI. Detection of dipentene. 
As already mentioned, pure cineol possesses the specific gravity 
0,9267, the portion identified by me as cineol showed the specific 
gravity 0,9024. This important difference in the data must, I think, 
be attributed to the fact that in the fraction under consideration a 
terpene was present (viz., limonene or dipentene, which both possess 
the specific gravity 0,844) which passes over with cineol at the same 
temperature. In order to detect the presence of this compound, the 
tetrabromide was produced. 
According to Wall a ch, it is prepared by dissolving the terpene in 
glacial acetic acid and adding bromine; but this method necessitates 
an absolutely anhydrous substance, so that the experiments made by 
this process were all unsuccessful. 
