ODOUR AND THE IMAGINATION 27 
WuatT 1s Opour or PERFUME ? 
Now let us ask ourselves what odour or perfume 
really is. Iasked a very celebrated chemist this question 
the other day, and he said frankly that odour, like elec- 
tricity and many other things, was a very subtle and 
‘‘unknown quantity,” and that no one knows absolutely 
and precisely what it is, nor why one odour should 
please us, and actually invigorate or stimulate us, while 
another disgusts us so much that we sometimes call it 
by another name. Odour seems a product given off by 
the action of oxygen on essential oils—a vapour being 
evolved under certain physical conditions of heat, moisture, 
or pressure, and even light and darkness now and then 
have some share in its evolution. 
PERFUMES OF FLOWERS 
Recent investigations have shown that the perfumes 
of flowers are often modified by growing them under 
coloured glasses, that some plants are fragrant only at 
night and others only in hot sunshine, that the seasons 
affect the odours, and that temperate climates are more 
favourable than tropical ones. A science paper says that 
these perfumes powerfully affect the human organism, 
often producing a kind of intoxication, and sometimes 
even giving rise to serious nerve troubles. The vapours 
of most essences—such as Cinnamon, Lavender, and 
Eucalyptus have proved powerful antiseptics, and 
flowers of delicate perfumes quiet the nerves of invalids. 
Flowers harmful to the sick, we are told, on the other 
hand, are the Violet, Lily of the Valley, and Oleander. 
OpouR AND THE IMAGINATION 
An American psychologist recently tried a curious and 
interesting experiment upon an audience chiefly composed 
of the members of the University of Wyoming. The pro- 
