cluded by glass cases while the weighing goes forward. The "Refinery" is a separate building in the rear, seven stories high, erected for this particular purpose. A section of the great "melting-room," with its furnaces and huge iron pots, together with an array of crucibles above, and gold and silver bars and boxes of granulations on little miniature cars below, may be seen and studied in the accompanying illustration.
THE GOLD REFINERY.
The operations of this department are too multifarious and complicated to be explained with the pen in our limited space. At every step in the work of assaying the metal is weighed by responsible officials, and every grain is rigidly accounted for. The "boiling-room" is in an upper story, and, rough as it seems, is one of the most interesting in the building, its office being to give us the gold and silver pure and true. Each kettle has a great leaden hood, since the vigorous chemical process evolves copious fumes of sulphurous acid. The gold contained in the granulations, not being soluble in sulphuric acid, is left from the cooking in the form of a yellowish brown powder, of which one tub often contains half a million dollars in value. The silver is washed with hot water, and squeezed into the shape of an old Dutch cheese by means of a powerful hydraulic press; after which it is dried in a steam-heated oven, and finally melted into bars of nearly pure fine metal. The gold is likewise washed, pressed, dried, melted, and
