22 Extracts from an Itinerary of a Journey in Spain. 
They were worked at a very remote period, since, according to 
Pliny, the Greeks obtained vermillion from them seven hundred 
years prior to ourera. ‘T'he same author tells us they were also 
worked by the Romans, and that Rome drew anny: from them 
one hundred thousand pounds of cinnabar. 
I found the business of the mines in the most leushind situation. 
At the period of the year when the laborers are the most active, 
more than seven hundred workmen, who succeed in each in three 
different divisions of the twenty four hours, are employed in the va- 
rious subterranean labors ; two hundred more work on the surface, in 
extracting, transporting, &c. Numerous muleteers are constantly 
occupied in carrying the mercury to Seville, and in bringing back 
to the mine, iron, wood, powder and provisions of all sorts. The 
veins are so productive that notwithstanding that the operations have 
been carried on during so many centuries, they have not yet attained 
a depth of three hundred metres. In the workings now going on at 
the bottom of the principal vein, the mass of ore, which is free from 
unproductive portions, is from twelve to fifteen metres thick: and 
this thickness is still greater at the point of intersection. The 
whole mass of the vein is taken out and immediately treated in the 
distilling furnace, without any kind of mechanical preparation. It 
yields ten per cent of mercury, but the medium production is prob- 
ably considerably higher. 
Mercurial ore is obtained, not only i in the mines just spoken of, 
but at a great number of points, in the direction of a zone which, 
passing through Almaden extends, like the principal veins, from 
east to west over a length of two myriametres, from the village 
of Chillon to beyond Almadenejos. This last village is itself the 
center of important mineral operations. Several mines, in the neigh- 
borliood, furnish ore like that of Almaden: they formerly were very 
productive, but the old veins being nearly exhausted, little is doing 
now except in extending the research. 'The furnaces of Almaden- 
ejos are fed, almost exclusively, by an ore recently obtained on the 
east of the village: it is a black schist, strongly impregnated. with 
metallic mercury, and in which very little cinnabar is visible. 
These ores are treated in thirteen double furnaces called Buy- 
trones in which the reduction is effected by the Spanish process and 
in one large quadruple furnace, recently constructed on the model of 
that of Idria. * The enclosure containing the metallurgic works of 
Almaden, includes eight Buytrones with the Idrian furnace. The 
five other Buytrones are at Almadenejos. 
