40 BOTANY. 
SuGAR occurs in many species of plants, and appears under three 
principal forms: cane sugar, grape sugar, and mannite. Cune sugar, 
C'*, H’, O° + 2HO, ts obtained from many plants, as sugar cane, beet root, 
sugar maple, birch, &c. It is soluble in about one third of its weight of water, 
and insoluble in pure alcohol. Grape sugar, or glucose, C'?, H'2, O'? + 2HO, 
is found in grape and other juices.. It can be prepared from starch or cane 
sugar by boiling in dilute sulphuric acid. Mannite, C*, H’, 0%, the chief 
ingredient of manna, a substance derived from several species of ash, differs. 
from the others in not undergoing the vinous fermentation. It is also found 
in the juices of celery, mushrooms, &e. 
LigNINE occurs abundantly in woody fibre, and is. distinguished from 
cellulose in being soluble in strong nitric acid, forming oxalic acid. Its 
formula is C*, H*4, O79. All these substances are readily convertible into 
each other. Some other ternary compounds of this character are salicine, 
found in the willows, and phloridzine, obtained from the bark of the roots of 
the apple, &e. 
There are other vegetable products which differ from these last in the 
presence of nitrogen. Thus gluten is that part of wheat flour which 
remains after the removal of the starch. Vegetable fibrine is obtained by 
treating the glutinous part of wheat with ether. Vegetable cascine, or 
legzumine, is found in oily seeds, and in leguminous plants. Vegetable albumen 
occurs as a soluble substance with caseine. It coagulates at a temperature 
of 140° to 160° F., and is not precipitated by acetic acid. The base of all 
these substances is proteine (C*°, H*', N*, O'*) Fibrine is_ proteine 
+S+Ph. Albumen is proteine +S*+ Ph. Caseine is protene +58. 
Emulsine, or synaptase, is found in almonds; and in bitter almonds is 
associated with a substance called amygdaline. Diastase is a modification 
of gluten, obtamed from malt, and developed generally during the germina- 
tion of plants. It facilitates the conversion of starch into dextrine, and thence 
into sugar. 
Fixep Ors occur in the cells and intercellular spaces of various parts of 
the plant. They are known by their greasing paper permanently. The principal 
are linseed oil, olive oil, and certain solid oils, as palm oil, shea butter, and 
vegetable tallow. These all contain a large amount of stearine. 
VEGETABLE Wax is a peculiar fatty matter found in the stem and fruit of 
some plants. On the exterior of fruits it constitutes their bloom, as m the 
grape and plums. Chlorophyll is allied to wax in character, being soluble in 
ether and alcohol, and insoluble in water. 
Voiatixe, or Essentia Orns, are procured from such plants as contain 
them by distillation in water, and are known as essences ; they do not grease 
paper permanently. Usually they are ready formed; sometimes, however, 
they are produced by a kind of fermentation. Some essential oils consist 
of carbon and hydrogen, as oil of turpentine, oil of juniper, oil of lemons, 
&e. A second set contain oxygen in addition, as oil of cinnamon, otto of 
roses, oils of peppermint, of caraway, and of cloves. Sulphur enters into 
the composition of a third set, which are distinguished by a peculiar 
pungent, and sometimes alliaceous smell, as oils of garlic, of onion, of 
40 
