20 INTRODUCTION. 
Endogens into close contact; besides breaking up the natural alliances 
of each, soas to scatter widely apart the members of groups nearly united- 
IDEA OF NATURAL ARRANGEMENT. 
21. The Natural system, on the other hand aims to present an 
harmonious and consistent view of the vegetable kingdom, by associating 
into orders those genera which agree in the most numerous and impor- 
tant characters, and which differ from others in the same. A table of 
the characters of these orders would therefore resemble the table of 
contents of a well-arranged book: giving at one glance to a person at 
all acquainted with the subject, an idea of the mode in which it is 
treated by the author, and of the relations which the several divisions 
of it had in his mind; and enabling a person who is entering upon the 
study of it, to do so with the knowledge that he is not gleaning at 
random, as if he were reading through a Dictionary, but that every acqui- 
sition he makes of an individual part, is something toward an acquaint- 
ance with the plan of thewhole. One more illustration may set this matter 
in a still clearer light. The reader may be requested to consider this 
series of treatises as completed according to the original plan; and as 
consisting of a number of volumes, each devoted to some particular 
science, but all having a certain degree of connexion with each other. 
Each volume consists of a series of chapters, in which the sub-divisions 
of these sciences are respectively treated of, and among which there is 
a still closer degree of connexion. Every chapter again, is made up 
of a number of paragraphs, each intended to contain one or more im- 
portant facts, the knowledge of which is in itself useful, but which can 
only be fully understood when read continuously with the preceding 
and following paragraphs. We shall further suppose that the subject 
of every paragraph could be concisely expressed by a single word. 
Now we will imagine these paragraphs all printed on separate slips of 
paper, with their appropriate titles to be given to a man of science, 
with a request that he would arrange them for publication. His first 
idea might perhaps be, to place them in alphabetical order, so as to 
form a kind of Dictionary ; this being the most easy method of fulfilling 
his task, and also having the advantage when complete, of admitting 
very easy reference to any required subject. But what idea would the 
reader of such a volume gain of the plan which the original author had 
in his mind? Or what connected and harmonious scheme of knowledge 
could he frame from them, unless he digested and arranged them in his 
own mind, in the manner in which we shall suppose our man of science 
to proceed to do? He might commence in two ways :—either by 
separating the whole into heaps, according to the subjects to which 
they respectively refer, e.g. Mechanics, Chemistry, Geology, Botany, 
