280 J. P. Kimball—Grahamiite in the Huasteca, Mexico, 
such specimens as I have seen, really being grahamite and other 
less thoroughly altered asphalts.* 
Judging from a number of specimens of these outcrops from 
farther up the Capadero than the district visited by me, as well 
rom such facts as I could gather by inquiry, it seems most 
probable that the shales of Tempoal and of the Cristo Mine, 
which came under my observation at these and other points in 
the banks of the Capadero, extend, at least, some 60 miles 
farther up the river, as far as Chalma, so as to include the so- 
called coal deposits at the base of the Cochiscuatitlan hills 
mentioned by Antonio del Castillo, viz., Purisima, Providencia 
and Virginia. A specimen of grahamite, now if m posses- 
sion, from Huautla, 50 to 60 miles still farther up the river, 
suggests a still greater extension of the same shales, found to be 
the seat of grahamite at Tempoal and elsewhere. 
Except in the banks of the river, and the beds of branching 
arroyos, the grahamite-bearing shales nowhere come to the sur- 
face in the Capadero basin, within the range of my observation, 
although not far below the level of the valley-plain, or lower 
terrace of the river. Together with grahamite, they are repo 
and may be readily believed, to outcrop in the Huejutla Moun- 
tains, as at the Venados, where a deposit of the former was 
described by the messenger sent thither for specimens, to be 
upward of two feet in thickness. 
ately overlaid by the heavy deposit of fine alluvium, the least 
thickn 60 feet. 
the Cristo Mine, it is near the water’s edge, though rising 
rectly on either side. We have as yet no data adil 
thickness of the shale, as its edges are everywhere concea® 
not by overlying alluviums—by a detritus resu 
own weathering, as it slacks at once on exposure to 
* Some attention of late, in the City of Mexico and elsewhere, has oe extent 
to this region upon the strength of rather venturesome comput of what is 
and value of the alleged coal deposits, based upon unexplored outcrops Criaderos de. 
assumed to | of bituminous coal. (Compania Explotadora bee 
Carbon de Piedra, Mexico, 1876. A report by Antonio del Castillo.) 
the alr. 
