DON FELIX D'AZARA. 31 



Under the head of minerals, an account is given 

 of what would now universally be regarded as a 

 meteoric stone, but the true character of which, at 

 the time, was quite unknown. In bulk, it was cal- 

 culated to contain about 470 cubic feet. The first of 

 these stones which attracted particular attention, as 

 elsewhere noticed in the Naturalist's Library, was 

 discovered nearly at the antipodes, and was brought 

 into notoriety by the eminent Pallas. The mass 

 before us shortly after attracted attention. Some 

 notice was taken of it in the 78th volume of the 

 Philosophical Transactions, and its constitution was 

 examined by Proust in the Journal de Physique for 

 1799. Azara's account of the immense rivers which 

 drain these countries is peculiarly ample and inte- 

 resting. The waterfalls bear their full share. We 

 shall allude only to his notice of the one on the 

 Parana, which afterwards, changing its name, be- 

 comes La Plata. Near the fall the river is very 

 deep, and is 12,600 feet across. Suddenly the 

 breadth is reduced to the space of 180 feet, and 

 in these circumstances the whole mass precipitates 

 itself with irresistible fury. It falls 52 feet, in a 

 plane inclined at an angle of 50 degrees with the 

 horizon. Azara compares this fall with the others 

 he describes in South America, and with that of 

 Niagara. All the others, he says, are inferior, as 

 to the quantity of water to Niagara, and to this of 

 the Parana. But none of them can be compared 

 with this last, if we consider that it does not pre- 

 cipitate itself, like the Niagara, in a simple and 



