APPENDIX. ' iS; 
either hot or cold ; and at the diftance of about two leagues to 
the eaft of this mafs, I difcovered a brackifh mineral fpring, 
the only one to be found in all this country. In the whole 
diftri<3: of the Chaco I travelled over, I obferved no difference 
in the level of the ground, except the very fpot where I 
made this difcovery ; and here only I found a gentle af- 
cent running from N. to S. and which attracted my no- 
tice before I had feen the mafs of iron. This afcent is 
between four and fix feet above the reft of the country. 
The earth in every part around this mafs, as well as about 
the brackifh fpring, is a very light, loofe earth, like afhes, 
even in colour. The grafs produced immediately contiguous, 
called Ahivi, is fhort, fmall, and extremely unpalatable to cattle ; 
whereas the grafs found in the reft of the country, at a little 
diftance from the mafs and fait fpring, is long and very grate- 
ful to them. 
At a little depth in the earth are found ftones of quartz, 
of a beautiful red colour, which the honey-gatherers make 
life of as flints to light their fires. They had formerly 
carried fome of them away, on account of their peculiar 
beauty, being fpotted and ftudded as it were with gold. 
One of thefe, that weighed about an ounce, came into 
the hands of the Governor of Santiago del Eftero, who told 
me, that he ground it, and fhewed me more than a drachm 
of gold that he had extracted from it. 
It is 'an undoubted fact, that in thefe immenfe forefts there 
exifts a mafs of pure iron, in the ftiape of a tree, with its 
branches. Many of the Indians have feen it ; and the inha- 
bitants of the colony of the Avipones, are acquainted with 
the fpot where it lies. A diltinguifhed European of the city 
B b 2 of 
