EXPORT OF QUICKSILVER. 217 
the furnace is the most hurtful process, the men 
employed working short spells, and resting a day 
or two between. A furnace charged with ore, I 
am told, takes about eight days to sublime and 
cool. 
It is difficult to obtain a correct statement of 
the absolute yield of this mine; proprietors, for 
many reasons, deeming it inexpedient to let 
~ the world know the extent of their riches. The 
export of quicksilver from San Francisco, a few 
years back, may, I think, be averaged at 1,850,000 
pounds of mercury per annum, valued at 683,189 
dollars; and this, together with the large amount 
consumed in California, was the sole produce of 
the New Almaden mines. . 
There are fourteen furnaces, arranged with 
passages ten feet wide between them, the whole 
covered with a roof sufficiently high to allow 
a current of air to circulate freely. Between 
the furnaces and on all the open spaces are 
innumerable bricks, just as.we see them in a 
brickyard to harden before baking. On inquir- 
ing what these were made for, I discover that 
all the fragments and dust-cinnabar are pounded 
together, mixed with water, and made into bricks: 
in this form the ore can be conveniently built into 
the furnace, securing intervening spaces for the 
