114 GENERAL SUMMAYB. 
are put down at prices nearly double those for the same char- 
acter of work in the United States. But even were the Tehuan- 
tepec road to exceed three or four times the estimated cost, the 
certain income derivable from its opening would more than jus- 
tify the outlay. 
In estimating for the equipment, a basis has been made upon 
a certain number of passengers, who have actually passed over 
the different routes to and from California for the last three 
years, and upon a certain yearly average of tons known to 
double Cape Horn, which it is but reasonable to suppose would 
take the Tehuantepec route, when established, in preference to 
any other. I am free to acknowledge, however, that the esti- 
mate of equipment is extremely low, and that great additions 
will necessarily be made from time to time as trade increases. 
Yet while I have endeavored to limit the number of engines and 
cars so as to fall on the safe side, it is difficult, indeed, to calcu- 
late with any degree of certainty on the amount of business the 
road will command, when an uninterrupted communication be- 
tween the two oceans shall have been effected. 
The next point which claims attention is the amplitude and 
security of the harbors, and the capacity of the rivers for ship 
and shoal-water navigation. First, then, with regard to the 
Coatzacoalcos. The fact of there being no delta at the mouth 
of the river, and the constancy of the depth upon the bar, which 
has remained unchanged, according to the history of the coun- 
try for nearly three centuries, proves that it has attained its 
" regimen" and indicates that any improvement by deepening 
the channel may be relied on as permanent. Of the precise 
character of the formation of this bar, many opinions are enter- 
tained ; and although its position and circumstances seem hard- 
ly to justify the conclusion that it is rock, Mr. Temple has so 
stated, and I have consequently consulted Mons. Maillefert (a 
gentleman whose experience in marine blasting entitles his 
views to credit) with reference to the possibility of deepening 
the channel to 18 feet, which, for a width of 300 feet, he esti- 
mates at $135,000. If Mr. Temple's impressions are correct, 
this item of cost, in connection with the importance of a perma- 
nent depth of 18 feet on the bar, can hardly be considered as one 
