M. Girard on Navigable Canals. 12t 
always been supposed that the navigation in the two opposite 
directions was equally productive ; a moment’s attention to 
the subject will suffice to shew that this supposition is not 
conformable to reality, that the weight of articles transport- 
ed downwards is far greater than that of the merchandize 
which ascends the canal ; and that this difference is likely 
always to exist wherever civilization is sufficiently advanced 
to render canal communications necessary between differ- 
ent sections of a country. 
The greatest population of a country always fixes itself 
at a point where the articles of first necessity which it con- 
sumes, and the raw materials which it employs in its man- 
ufactories, can arrive with the greatest facility. Navigable 
rivers offer so great natural advantages for this object that 
they have drawn to their banks a great number of inhabi- 
tants ; in this manner the valleys are covered with cities, and 
the capital of a country is generally situated on the banks 
of the largest river which passes through its territory. 
When the population of the valleys through which the 
navigable rivers run, becomes so dense that those valleys 
ean no longer furnish sufficient means of existence, recourse 
must be had to the more elevated plains to supply the defi- 
ciency, and sometimes certain productions of the earth are 
drawn from the mountains to be employed by the hand of 
industry. In these circumstances artificial canals become 
necessary for the transportation to the place of consumption, 
and without greatly enhancing the price, of grain, drink, 
wood, timber, and other materials for construction, as well 
as pit-coal and iron castings, those two sinews of manufac- 
turing industry. But these productions of the earth, which 
descend to the valleys, are incomparably heavier than the 
manufactured objects for which they are given in exchange. 
Thus we see that the boats which transport coals and cast- 
ings from Birmingham to London, descend the canals deep- 
ly laden and return empty to seek new cargoes; and, with- 
out going out of our own country for examples, is it not the 
same on the canal of Givars in the vicinity of Lyons? and 
do we not every day see that the boats which supply Paris, 
arrive with full cargoes, and, after discharging them, as- 
cend the Seine or the Marne almost entirely empty? A 
great number of these boats, especially those which come 
from the centre of France by the canal of Briare, do not 
Vou. IV.....No. 1. 16 
