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 1,350,000 

 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 



