OF THE MINERAL WORK.

vessels. There is, however, another mode of extraction, which is done in the cold without glass vessels, which I also thought worth the effort to set down, so that you may choose this one or that one at your pleasure in the aforementioned work, which is performed by the following path. We have, however, need in this mode for a quantity of earthen funnels, well baked, not absorbing the spirit of salt; in the defect of which, strong glass ones should be procured. There is also required a bench provided with many holes for receiving the aforementioned funnels, beneath which glass bowls are also substituted to receive the percolated spirit of salt.

Once the funnels are placed in the holes of the bench, it is first necessary that a small coarse fragment of flint be placed in the narrower part, upon which smaller ones are afterward placed, and upon these again smaller ones, as much as is sufficient for the filling of the narrow part of the funnel, the wider part of which is afterward to be filled with pulverized flints, yet so that a space of 3 or 4 transverse fingers is left for the spirit of salt. By this method, those coarse particles placed in the lower part prevent the passage of the finer powder of the flints during the pouring on of the spirit of salt.

Which things being duly performed, pour spirit of salt onto the flints contained in the funnels to a height of 2 or 3 transverse fingers, which will immediately attack them; the gold contained in them will be attracted,