CHEMICAL COMPOSITION OF THE SAP. 
147 
ciples show how wide a field is open to the chemist, in the study 
of vegetable elements. 
It may seem wonderful, that of so few elementary substances, 
such a great variety should exist, in the taste, smell, colour, 
consistence, medicinal and nutricious qualities of vegetable com- 
binations ; is it not equally wonderful that, with the nine digits and 
the cypher, we may make such varied combination of numbers ; 
or with our twenty six letters of the alphabet, form every vari- 
ety of composition ? Thus, by the various combinations of a 
few simple principles, are formed all vegetable and animal pro- 
ductions ; and, although formerly, the presence of nitrogen was 
considered as a test of animal substance, and the want of it, of 
a vegetable substance, it is now ascertained that animal substan- 
ces may exist without nitrogen, and that this principle is con- 
tained in several vegetable substances. 
The elements of the compounds being the same, the question 
naturally arises, what caifSes the great diversity in the proper- 
ties ? Two causes may be assigned in answer to this question, 
viz. 1st. The different proportions in which the elements are 
combined. 2nd. The various modes of their combination. 
In vinegar and sugar, the one substance a liquid, and of a sour 
taste ; the other solid and sweet, are found the same elements in 
different proportions and differently combined. In gum, starch, 
and sugar, the elements are the same, the proportions nearly 
the same, but they are combined differently. 
When we know by chemical analysis, the combinations which 
exist in inorganized bodies, we can by putting the same togeth- 
er, often form similar substances ; but we cannot thus form or- 
ganized bodies ; for to these belongs a living principle, which it 
is not in the power of man to bestow. It is said that Rosseau 
declared he would not believe in the correctness of the analysis 
■*of vegetable or animal substances, until he should see a young 
animal or a thrifty plant spring into existence, from the retort 
of a chemist. But the power to create, the Almighty has not 
delegated to man ; neither is it to be supposed that any future 
discoveries in science, will ever confer it upon him. To study 
into the compound nature of substances, to classify, arrange, and 
by various combinations to beautify the world of matter ; to 
cultivate the faculties of mind, until stronger and brighter, the 
mental vision sees facts and principles before invisible ; these 
are the high privileges bestowed on man ; but to add one new 
particle to matter, or one new faculty to the mind, is beyond the 
power of the whole human race. 
