900 
Proceedings of Royal Society of Edinburgh. [sess. 
pores of the cell. Camphor, for instance, comes freely through the 
walls of the cell, hut at first only in small quantity ; but the smell 
outside becomes stronger with time, and if the camphor he removed 
from the interior of the cell, the outside of the cell continues to give 
off the smell of camphor for days. Some of the camphor is evidently 
condensed in the pores and is slowly given off, just as water vapour 
is condensed and slowly given off under similar conditions. Both 
the filter and diffusion tests were, however, used in some cases 
as checks on the condensation method. 
The following table shows the substances tested. Many of 
them are entered under their ordinary commercial names. All 
of them, with the exception of the metals, flowers, and herbs, were 
tested in the apparatus shown in the figure. For testing the 
metals, etc., a larger flask than B was used. The metals were 
in the form of wires — a quantity being coiled up and placed in 
the bottle. The result of the tests was that not one of the 
twenty three substances gave off their perfume in solid particles, 
nothing hut gases or vapours escaping from them. 
List op Substances Tested. 
i 
Natural Products, . . 
Chemical Products . . j 
Metals, . . . . | 
Flowers, . . <| 
Herbs, . . < 
Asafoetida gum — ground. 
Caraway — ground. 
Cinnamon „ 
Cloves. 
Cubebs ,, 
Lavender. 
Nutmeg ,, 
Pimento ,, 
Tobacco „ 
Sewage. 
Stink-wood (Kaizer Busuk). 
Ammonia carbonate. 
Menthol. 
Zinc valerianate. 
Brass. 
Copper. 
Iron. 
Lilies. 
Boses 
Sweet-peas. 
Peppermint. 
Kue. 
Sage. 
