M. Girard on Navigable Canals. 121 
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 heegseery between differ- 
ent sections of a country. 
The greatest population of a country always fixes tse 
at a point where the articles of first necessity which it 
sumes, and the raw materials which it employs in its ada 
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 covered with cities, and 
the capital of a country is generally situated = the banks 
of the largest river which passes through its territory. 
When the population of the valleys hci 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- 
ons of the earth are 
ciency, and sometimes certain a 
drawn from the | to be employed by the hand of 
industry. In these circumstances artifie ial canals become 
necessary for the transportation to the place of consumption, 
and without greatly enhancing the price, of 
wood, timber, and other materials for construction, aswell 
as pit-coal and iron castings, those two sinews of manufac- 
SS - But these productions of the earth, which 
descend to the valleys, are incomparably hea vier than the 
manufactured objects for which they are given in ee 
Thus we see that the boats which transport . 
out going out of our own country for examples, is it a 
same on the canal of Giyars in the vicinity of Lyons? and 
do we not every day see that the boats: which sopply: Paris, 
arrive with full cargoes, and, after ae u nem, as- 
eat number of these boats, . especially those those which come 
fom the centre — Dy ie ean of Bar, don 
ee 
