Manufacture of Sulphat of Iron. 328 
nel, into which by its inclination the mine discharges the 
wash of every shower, together with the natural oozing 
from the hill above. A trough conveys the fluid from the 
channel to the boilers. To increase the effect of this natu- 
ral brook of copperas, the ore has been broken into large 
fragments, and heaped along the upper side of the chan- 
nel, there to undergo a slow decomposition precisely as it 
does upon the scaffolds mentioned above. 
_ The mine where it has not been opened is covered with 
oxid of iron which consists principally of incrustations of 
vegetables. 
n the part where 1 examined these incrustations they are 
about three feet deep. The vegetables seem to have been 
enveloped by a thin uniform crust, but having decayed and 
disappeared the crust remains an empty mould or pattern of 
the vegetable. The general figure of the vegetable is pret- 
ty well preserved in the external form of incrustation ; but 
the internal cavity is wonderfully perfect, the sinuosities 
of the bark, the veins of the leaves and the strie of the 
buds are preserved to microscopic minuteness. The im- 
pressions are so perfect that it is difficult for one to con- 
vinee himself that the real vegetable is not there. All the 
vegetables that we should onpecsat a aoe oo 
of ‘ground, ini the woods, seem to occu 
general recognize the species and even erat earag 
Among the specimens I obtained were the following : hem- 
k branches and cones; nuts, burrs, and leaves of the 
beech ; hazel nuts and a species of golden rod which I re- 
cognized by a peculiar ss ae often produced upon this 
-by an insect. Icould not ascertain that any animals 
had ever been found i he The incrustations are divi- 
ded into several Strata by Jayers of oxid, which have a 
Ser eee Te nt a fracture almost a 
The wikia as told me that four men 
one hundred tons of co; in a year, beside ering on 
ry rich. The sup rel 
afforded three hundred srl sthirey-abree mckemragncens 
be 8 Ill... No. 2. 42 
