20 ENGINEERING- REPORTS. 
of its course being too precipitous, and having near its mouth 
a fall which impedes the entrance of canoes ; but the Jumuapa 
can be ascended in the rainy season to a point known as the 
Paso de la Puerta, from which there is a good mule-road to San 
Juan Guichicovi. The Jaltepec Kiver has its source in the Sierra 
of the Mijes, situated in the district of Yilla Alta, and is navi- 
gable for canoes all the year round to a spot called Tutla, about 
fifty miles from its mouth. This river is nearly as large as the 
Coatzacoalcos above the confluence of the two streams, and is the 
most important tributary on the west. The Chalchijapa is also 
a considerable stream, and the Indians ascend it for five days 
with rafts, and then cross by land to the village of Santa Maria 
Chimalapa. Between the confluence of the Chalchijapa and 
the point of La Horqueta, where the river divides into two 
branches, the small streams Colorado, JSTaranjo, Penas Blancas, 
and Cuapinoloya join the river by its left bank, and the Chur- 
riagao by the right. The general course of the Coatzacoalcos 
from the confluence of the Malatengo to that of the Jumuapa, 
is from south to north : it then runs northwest until it meets the 
Jaltepec, and thence to the bar its general course is northeast. 
The length from the mouth of the Malatengo to the Sarabia is 
19 miles ; from the Sarabia to- the Jumuapa, 14 ; from the Ju- 
muapa to the Jaltepec, 10 ; from the Jaltepec to the Chalchija- 
pa, 14 ; and thence to the Horqueta, 38 — being 95 miles between 
the Malatengo and that point. 
Above the confluence of the Jaltepec, the country on either 
side of the Coatzacoalcos is more or less broken and hilly, and 
the banks of the stream often rocky and precipitous ; but be- 
low this point the margins are comparatively low, and the sur- 
face level for some distance back from the river. Between the 
Jaltepec and the Horqueta, there are a few spots called cerritos, 
or hillocks, composed of beds of clay, from 40 to 60 feet in 
height. The banks of the river, however, seldom exceed 10 or 
15 feet, and are sometimes so low as to be covered in times of 
flood. 
At the Horqueta, as has been said, the river branches — the 
western arm being called the Brazo Mistan, and the eastern the 
Brazo Apotzongo : these branches unite after having formed the 
