PHYSIOLOGY. | '93) 
§ 230. 
Ail the now enumerated principles which have 
‘been found in vegetables, belong, as far as chemical 
knowledge has advanced, to the elementary or sim- 
ple substances. The vital power produces by mix- 
ing them, new formed substances, which we cannot 
ae in silence. ‘They are the following : 
- Volatile oils, composed of carbon and _ hy- 
ee are found in all parts of plants, more fre- 
quently, however, in warm than in cold climates. 
2. Resins, are met with in the roots, bark, wood, 
and in the blossoms,and fruits of many plants; and 
likewise more frequently in those of warm than of 
cold climates. 
3. Gum-resins, or such as are composed of gum 
and resin. Apothecaries use many of them, ec. g. 
the gum Asafoetida, (Herula Asafoctida) ; Gamboge, 
(Stalagmitis guttifera) 5 en storax, (Styrax of- 
fecinalis), and others. 
4. Camphor. ‘This substance we obtain from the 
camphor-tree, Laurus camphora and many other 
species of laurel, c.g. from the old roots of the 
cinnamon-tree, (Laurus Cinnamonum), and others. 
Camphor has likewise been found in some of the 
essential oils. 
5. Fixed or fat oils. These occur in the fruits 
of many plants, e. g. in almonds, (Amyegdalus com 
munis); in the walnut, (Juglans regia); in the olive, 
(Olea europea); in the Ricinus communis, &Fc. - 
6. Wax. is likewise found in the fruits of some 
plants, ¢. g. of the laurel, (Laurus nobilis), and of the 
Myrica cerifera and others. We have it in the pol- 
P 4 len 
