1889. | NEW YORK ACADEMY OF SCIENCES. 165 
destined to be of priceless value to the people of America,—over 
which a great railway is some time to be built, which will unite 
the railway systems of North and South America. Happily, 
without altering its character as a bridge uniting the northern 
and southern continents, interoceanic highways for ships can be 
built across it. 
The part of the American isthmus which belongs to Mexico 
is called Tehuantepec. In the year 1847, the President of the 
United States offered to make with Mexico a treaty by which our 
Government would pay fifteen millions of dollars for Tehuante- 
pec. Fifteen millions of dollars, at that time, represented to 
the Government of the United States a vastly greater sum than 
it does at the present day. Buta far-sighted statesmanship justly 
recognized this as a geographical position of great value to the 
people of North America. 
After expensive surveys, it was discovered that however great 
would be the distance saved by vessels of the United States en- 
gaged in coastwise and foreign trade, could they be borne across 
the northern part of the American isthmus instead of having to 
make an immense detour of the entire continent,—or to sail many 
hundreds of miles southwardly to enable them to cross the isth- 
mus at Panama or at Nicaragua,—a ship canal at Tehuantepec 
would have to be constructed over an elevation of between seven 
and eight hundred feet above the sea, and would require between 
one and two hundred locks,—in short, that its construction might 
be justly considered as almost or quite impracticable. But the 
late Captain James B. Eads raised the question whether science 
is not equal to devising a better means of transit for ocean 
vessels across the American isthmus than the best of canal navi- 
gation could afford. 
One peculiarity believed by many travellers to characterize the 
oriental nations, is that the people, for generation after genera- 
tion, use only the same mechanical contrivances that were em- 
ployed by their fathers. For many hundreds of years canals 
have been used as highways for commerce in different parts of 
the world; and these were found, for certain purposes, an im- 
provement upon roads. The famous canals of China have done 
much to bind together many of its widely separated sections of 
country, and long before America was discovered by Columbus 
they might well have filled Europeans with admiration. Many 
people may be surprised to hear that the freight-boats which are 
constantly plying upon the rivers and artificial water-courses of 
China, are so great in number, and her inland commerce of such 
stupendous dimensions, that it has been said to have a greater 
amount of tonnage than all the other nations of the earth com- 
bined. The canal-system of China, however, is in various respects 
