Miscollaies.  @ 2ar7 
to have been lost, for although resinous, it burns without flame. 
From personal examination of the country, east of the sandstone ele- 
vations, Mr. Blake concludes that a lake of considerable extent once 
covered the space between these and the CordiJleras. Numerous vol- 
canic rents now exist among the_mountains, and it is probable that 
the saline matter produced by them was dissolved in the water, form- 
ing a lake at the base of the mountains. This lake subsequently 
broke its barriers, and prostrated a forest then growing where the 
saline matter is now found. I have carefully examined the earthy 
matter which is mixed with the nitrate of soda from different parts 
of the province of Tarapaca, and find that the larger part is com- 
the washings of sandstone,—these facts I consider as supporting the 
conclusion of Mr. Blake. The surface of the pampa is mostly sand, 
clay, and saline matter. The latter is composed of sulphate of lime 
and soda, salt, and nitrate of soda—some parts present the nitrate of 
soda at the surface—at others, a few feet below. These salts have 
all the physical and chemical characters of salts produced by decom- 
position and separated by evaporation from solutions. The nitrate of 
soda is found in distinct strata, a thin layer of brown loam separating 
the parts; it is also found mixed with salt, and forming a small por- 
tion of the whole mass. The refining operations are rude and simple. 
The richest masses of the native salt are blasted or broken and divi- 
ded into small portions ; with these, copper kettles are in part filled, 
and water, or the mother water of former operations, is added, and 
heat applied until a boiling and saturated solution is obtained. The 
solution is transferred to wooden coolers, where the nitrate of soda 
crystallizes. The undissolved salt remaining in the kettles is thrown 
‘ ote fresh salt being used each time, although not one half o 
nitrate of soda is dissolved. The coolers are emptied after the crys- 
tals of nitrate have ceased to form ; 3 it is dried, packed in bags, and 
sent to the coast on mules. The wood used in the operations is 
transported from a distance on the backs of mules from the borders 
of the pampa. Of late, attention has been turned to using the alter- 
ed wood of the buried forest, and some excavations promised a sup- 
ply. Water is found by sinking wells in some places, below the sa- 
line soil. The subsistence of the workmen, drivers and mules, is 
mostly drawn from Valparaiso. The quantity of nitrate of soda 
which exists in beds is immense, and in addition it is probable that 
the saline soil would afford a large supply. 
Native nitrate of soda, in fractured masses, has a granular struc- 
ture, arising from the aggregation of irregular rhombic crystals, va- 
