The Sierra Blanca Pass is right at Tarifa, and its material is made up of soft calcareous tufa.
The Chichihua is 71 feet below the summit, and the Pericon is on the grade of the feeder, so that the length of cutting to Tarifa will be less than 10,000 feet, through easy ground, across the thin web-like spurs that divide the Tarifa and Chichihua potreros. The rise of the ground is gradual from Chichihua toward Sierra Blanca, and abrupt from north to east, as can be seen by the Pericon, which runs quite parallel to the Albricias Hill, up to Sierra Blanca. At this point it is sent northward, while the Naquipa runs north and south from the pass to the Chichihua. The Corozo route will require six miles of hard tunnelling, and seven miles of equally hard deep cutting. The direct route has five miles, requiring no extra cutting, and only three miles of heavy cutting, through soft soil, and in which a short tunnel will be found economical.
Since Tarifa River is lower than the Tarifa plantation, and the arroyo Pita is also lower than Tarifa River, it will be seen that there can be no doubt as to the possibility of supplying the summit with water, if it can be brought down to the Pita.
From San Miguel Pass and Cofradía we went to Santa Maria Chimalapa, where, after suffering many hardships, we were obliged to return to Chivela, and make such arrangements as would insure our passing through the Chimalapa region in order to reach the river Corte.