the soil, wood, metals,
imply the exchange of products; but this must obtain to a very limited
extent while neighbors are remote, and the means of travel and
transportation defective. With few roads, and commerce undeveloped,
there is little intercommunication, little culture, little civilization.
This was the condition of Scotland as late as the middle of the
eighteenth century. (Buckle.) England had some external commerce as
early as the thirteenth century (Hallam), but did not send a ship of her
own into the Mediterranean till the fifteenth. (Robertson.) Think of the
difference between then and now!

The making of tools, implements, and fabrics is at first carried on
solely by individuals working alone, but at length, machinery comes into
use, the elements are used as driving power, and manufacturing
establishments arise having a complicated organization. The division of
labor has been all the time becoming more complete, till now a single
workman manages but a part of the process of making an implement or a
fabric, which must pass through many hands in succession before it is
completed. All are familiar with this fact. It is exactly analogous to
that which we observe in the animal economy. Low in the zoological
scale, one membrane performs all the organic functions; higher in the
scale, there are different organs to perform the distinct functions.
When the stomach and liver first appear, they are very simple in
structure, and as simple in function; it is just so with the
manufactories in the industrial organism. But the stomach and liver
become more complicated as the scale rises; it is just so with the
manufactories as civilization advances. Animals lowest in the scale have
no heart--no circulation. It is just so with society--if society it may
be called--which is lowest in the scale; it has no exchange of
products--no commercial circulation. The parallelism is complete.

Further, as already specified, we find in the animal organism, that the
dependence of parts and functions upon each other becomes greater with
the increase of complexity; that unitization at the top of the scale, in
the midst of an almost infinite complication of organic structures and
functions, has a completeness and significance which it cannot have in
the simple organism at the bottom of the scale. The same precisely is
true of the social organism. At the bottom of the scale, there is no
dependence of one part on another--no cooeperation--no