51 
Escolapa as well as the Milagro, and the streams which unite 
with it, have their sources in the desert jDart of the Sierra to 
the east of the road which leads from San Miguel to Santa 
Maria Chimalapa. The course of the Malatengo and its tri- 
butaries are laid down upon the map. 
The hills on either side become gradually depressed, and at 
a short distance from the Escolapa they are very insignificant ; 
nevertheless the rocks before mentioned frequently show 
themselves, forming the rapids already spoken of, and which 
give rise to many windings, so that the course of the river be- 
tween the confluence of the Milagro and that of the Malatengo 
is 281 miles. 
Half way between the Escolapa and the Malatengo is the 
station of the Angostura, so called from two beds of greenstone 
rock rising in the middle of the river, whilst the banks of the 
stream, also of the same formation, are very precipitous ; so 
that the channel, which above this spot was 33 yards wide, 
becomes divided into three, the widest of which is only 5^ yards 
broad. This same rock is found in some of the rapids below 
this, but they considerably diminish in importance. 
As the Malatengo is approached, the hills reappear with 
more elevation and frequency on the borders, and con- 
tinue the same beyond its confluence. The accession of 
waters to the Coatzacoalcos is now more perceptible in its 
greater depth, which from this place to the mouth of the Sara- 
bia is generallyfrom 5 to 8| feet and sometimes even 16i feet 
deep whilst in its breadth, it does not exceed 44 yards. 
Next after the Malatengo the rivulet of rio Chico joins on 
the right bank coming from the Sierra of Chimalapa ; and at 
no great distance on the other side enters a stream, near which 
is an ancient wharf called Mai Paso, so named on account of 
a strong rapid a little below it, and which caused it to be 
abandoned. At the present day another loading place is call- 
ed by the same name, but this is 220 yards above the Paso del 
Sarabia close to the mouth of the river of the same name. 
This rapid, which is the strongest to be found after leaving 
Angostura, is formed of various ridges of calcareous spar and 
granite, and occupies a space of 200 yards. The first of these 
