28 
ENGINEERING REPORTS. 
character. From ten to twenty feet of the earth next to the sur- 
face can probably be moved with the pick and shovel, and rattled 
down into the ravines below. Nearly the whole of the slate for- 
mation is more or less traversed in various directions by small 
veins of quartz. 
It will be seen by the profile of the Masahua Pass, that the 
lowest declivity of the valley, with reference to grade, is at a point 
two miles from the summit, from which it increases from zero to 
150 feet ; thence decreasing to zero again, where the line enters 
the plains. 
Just before reaching Cerro Masahuita, we encounter a deep 
ravine, running parallel with the northern base of the mountain. 
The fill here for 700 feet will average 80 feet in depth : this cannot 
be avoided in running through Danta Pass. It may, however, 
be entirely obviated by running the line back of the mountain, 
and coming into the valley of " Torrente de Masahua" by the 
" Arroyo de Molino." At this point I have estimated for a wood- 
en bridge, with stone abutments and piers. From this fill the 
line sweeps around the end of " Masahuita" on a radius of 1000 
feet ; thence taking a westerly course along the southern slope of 
the mountain to the " Arroyo de Molino," which it crosses on a fill 
of 65 feet ; thence on to the southern slope of " Cerro Barnard" to 
Arroyo de„Juan, crossing on an elevation of 55 feet; thence con- 
tinuing along the southern base of Cerro Prieto, it reaches the 
Camino Real, descending through Chivela Pass, where the line 
crosses to the opposite bank of Torrente de Masahua, and contin- 
ues in the vicinity of this stream till it reaches a point opposite the 
extreme end of the bare hills called Cerro de la Martar, and, after 
recrossing what is now called Rio Verde, it passes by the Rancho 
de la Martar, over the plains to San Geronimo, Comitancillo, Te- 
huantepec, and lastly, to the harbor of Yentosa. 
This is the line surveyed west of the Coatzacoalcos, by way 
of the dividing ridge between the Jaltepec and Jumuapa, the 
Malatengo and the Pass of Masahua ; but it will not probably 
be the final location, as a better route undoubtedly exists east of 
the Coatzacoalcos, via the Almoloya and the Pass of Chivela. 
The reason for not surveying this line will be found in another 
place. 
