CHAPTER VIII. 
INTERURBAN AND CROSS COUNTRY WORK. 
The most important class of electric roads at present 
is that composed of tramways that have outgrown and 
reached beyond their urban starting points and serve to 
interlink cities and villages. These lines are important 
and interesting to the engineer, since they are often sub- 
ject to unusual conditions and require special treatment, 
and they are of immense value and importance to the pub- 
lic, because they tend to break down the industrial barriers 
that have been artificially established between city and 
country, and give to both some of the advantages now 
peculiar to each. 
There is nothing in the nation’s growth more menac- 
ing to good government and the healthy growth of industry 
than the rapid concentration of population and enterprise 
at a small number of overcrowded spots. 
The opening of easy channels of communication 
through the country at large, increases enormously the 
areas available for profitable manufacture and decent habi- 
tation. Much has already been accomplished by the in- 
terurban and suburban electric railway systems already 
installed, and much more can be done by the extension 
of these lines and the building of new lines through regions 
that are now isolated. 
Fig. 106, showing the connected system, of which Boston 
is the center, gives a vivid idea of the extent of country 
covered and the thoroughness with which the work of in- 
terconnection is done in certain regions. $Still, large dis- 
tricts are left untouched, giving ample room for further 
extensions. ‘The districts already interlaced, however, 
have an aggregate population of very nearly 1,250,000 in-