GENERAL SUMMARY. 
113 
that no difficulties exist in tlie way of constructing a railroad 
over those divisions which lie on either side of the dividing- 
ridge. It remains, then, only to speak of the practicability of 
the middle district, in which is comprised the route through 
the mountains, separating the two oceans. On every part of 
this, on the line of location, detailed estimates have been made 
of the earth to be moved, and the masonry and bridging to be 
constructed, all of which have been given in Tables marked Di- 
visions II., III., and IV., and indicate the extremely favorable 
nature of the work. Yet the quantities of graduation and ma- 
sonry laid down, for this as well as other portions, will be found, 
on the final location, considerably in excess, for the reason that 
the line surveyed is by no means over the best route. That 
other and better ones than this exist, there is little doubt, and 
but for the edict of the Mexican authorities, would have been 
examined. As our operations were therefore confined to a sin- 
gle line, it would be somewhat anomalous if, in view of the dif- 
ficulties which necessarily assail engineering operations in a 
country so entirely new as the Isthmus was to us, we had hit 
the most favorable ground in the offset of the work. The esti- 
mates have nevertheless been drawn up in the same manner as 
if no other or better line existed. It is consequently but rea- 
sonable to infer that a great reduction, in cost and quantities, 
will be made on the ultimate location of the road. 
The surveys over the Atlantic and Pacific plains bear more 
the character of reconnaissances than absolute surveys, and al- 
though compass and level lines were run over these portions to 
determine beyond question their entire practicability, detailed 
estimates and minute instrumental observations were not so 
necessary as on the middle division, where all the doubts and 
difficulties were centered. In this connection, moreover, it is 
well to bear in mind, that the New Orleans Company, in send- 
ing the expedition to the Isthmus, desired not so much to locate 
a line as to demonstrate the question of practicability within a 
reasonable cost, and the existence of efficient harbors at each 
termini of the road. 
With reference to the expense of construction, as already given, 
it is only necessary to say, that the items embraced in the table 
8 
