ENGINEERING EEPOKTS. 
20 
There seems to "be but two favorable localities for railroad 
crossings over the Tehuantepec River — one at the city of Tehuan- 
tepec itself, and the other just below Huilotepec : the former is 
by far the best. 
If the line should be located by way of Tehuantepec, it ought 
to pass between Cerro de San Diego and the ridge of Cerro Xu- 
nirahui. In this case it would necessarily cross the San Jone. 
Should it be thought advisable to run the line from the mouth 
of the Pass of Chivela,* by the most direct route to Yentosa, in- 
stead of by the towns just mentioned, it would go to Huilotepec, 
and then either cross the river Tehuantepec to the lower base 
of San Diego, and so sweep round under the Cerro Morro ; or, 
without crossing the river, keep its left bank to the sea. It is, 
however, better to cross the river, and run down near the base 
of Cerro Morro close to the site of the proposed breakwater, for 
by extending the breakwater from the end of Cerro Morro fifteen 
hundred or two thousand feet, it would afford ample protection 
to the wharves at this terminus of the road. 
The material on the Pacific plains is sand, gravel, red and 
yellow clay. The embankments over this portion of the route 
will not average more than two or three feet in height, and may 
be thrown up directly from the sides. 
The following extracts from the report of Mr. J. C. Avery 
embrace the details of the operations of the party under his 
charge, and a particular description of the line north of the di- 
viding ridge : 
"In compliance with instructions, I occupied a portion of 
the time that we were waiting canoe transportation, in making 
a reconnaissance of the country to the west of the Coatzacoalcos 
Eiver, from Mina-titlan to Mt. Encantada. In order to obtain 
some data on which to base an estimate of the probable length, 
and cost of a railroad to connect those points, I provided 
* The entrance to the Masahua and Chivela Passes from the plains of the Pacific 
ia a point common to both. 
