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artificial aromatic bodies, and the perfumery industry utilising the products 
of both, the lecturer discussed the first two in detail. 
The oldest, most largely used, and most improved method of 
obtaining flower-oils, is the method of steam-distillation, which pro- 
duces not only valuable oils, such as the oils of orange -flowers, roses, 
and lavender, but also aromatic waters. Chemical analysis of the 
numerous oils obtained by this process has brought to the light a large 
number of components, of which, in spite of the activity of scientific 
investigation of the present day, we have as yet no full and complete 
knowledge. By methods of examination of an increasingly detailed 
and exact character, it has in recent times been possible to isolate 
from many oils certain constituents which occur only in most sub- 
ordinate quantities, yet have an exceptionally important effect on the 
odour, — and to estimate the part played by them in the composition 
of the perfume. Such, for example, are nonylic 'aldehyde and other 
constituents in rose oil, or methyl anthranilate in neroli oil. Another 
process is the so-called enfleurage, based on the property which natural 
odours have, of becoming incorporated in fats. The enfleurage process 
is used especiall}' for flowers, such as the jasmine and tuberose, whose 
aroma is sensitive to high temperatures. The flowers are placed in 
vaseline or melted fat, or wrapped in cloth prepared with fat, and 
fresh quantities of flowers are constantly brought into contact with the 
fat until the latter is saturated. When clarified by filtration, the fat, 
laden with perfume, represents a most important article of commerce. 
By treatment with dilute alcohol (which does not dissolve the fat), the per- 
fume can be extracted from these flower pomades, and is thus offered to 
the perfumer in a convenient form. The most recent method is the one 
of extracting the aroma from the material by means of volatile solvents, 
such as ether, or more generally petroleum ether. On evaporating the 
latter, usually in vacuo, w^axy residues remain behind, from which, as 
in the case of pomades, the pure flower oil can be isolated in the most 
concentrated form without fatty secondary odours. 
The published statistics throw light on the great development of 
this industry in the departments of Southern France. In the com- 
petition with foreign products, the lecturer sees a great impediment in 
the high duty on alcohol, which frequently exceeds the value of tlie 
article itself, and he strongly advocates the complete or partial abolish- 
ment of this duty. 
For our present knowledge of the chemical composition of per- 
fumes and essential oils, so Dupont continues, we are indebted to 
the unexampled development of organic chemistry within the last 
decades. And whereas the first investigations in this domain were 
preferably carried on by French chemists, in recent times German 
chemists have taken a leading part. It is a matter of importance in 
