265 



pend on a great number of elements by their 

 nature variable, is the difficulty of fixing the 

 maximum which the efforts of intelligence and 

 the physical power of nations are capable of ex- 

 erting. During the thousands of years that 

 have elapsed from the unknown period of the 

 construction of the pyramids of Ghizeh, to that 

 of our gothic steeples and the cupola of Saint 

 Peter's, men have not raised one edifice exceed- 

 ing 450 feet in height * ; but shall we presume 

 to conclude from this fact, that modern archi- 

 tecture cannot go beyond an elevation scarcely 

 equal to forty times that of the edifices con- 

 structed by white ants ? If the question here 

 agitated respected only canals of a mean size, 

 having a depth of only from 3 to 6 feet, and 

 serving merely for inland navigation, I could 

 mention canals long since executed, which pass 

 over ridges of mountains of from 300 to 580 

 feet high-f. England alone, of which the canals 



* Ancient French measure, 'pied de Roi, or 75 toises. 



+ The following are the partial statements for ten canals, 

 arranged according to the order of the height of their points 

 of partition : — 



Elevation of the 

 NAMES OF THE CANALS. Points of Partition 



in French feet. 



Canal of Languedoc, or of the South. (Length, 

 123,730 toises ; mean depth, 6f. 2 in.) • num- 

 ber of locks, 100; expence of construction, in 

 the time of Louis the 14th, nearly 16,280,000 

 francs 5 at the present value of money 33 mil- 

 lions of francs. G. N 582 



