The quantity of water required for the effective treatment of gold-bearing rock in a stamper battery varies according to the composition of the material to be operated upon, but generally it is more than the inexperienced believe.  For instance, “mullocky” lode stuff, containing much clayey matter or material carrying a large percentage of heavy metal, such as titanic iron or metallic sulphides, will need a larger quantity of water per stamp than clean quartz.  A fair average quantity would be 750 to 1000 gallons per hour for each box of five stamps.  In general practice I have seldom found 1000 gallons per hour more than sufficient.

As to the most effective mesh for the screen or grating no definite rule can be given, as that depends so largely on the size of the gold particles contained in the gangue.  The finer the particles the closer must be the mesh, and nothing but careful experiment will enable the battery manager to decide this most important point.  The American slotted screens are best; they wear better than the punched gratings and can be used of finer gauge.  Woven steel wire gauze is employed with good effect in some mills where especially fine trituration is required.  This class of screen requires special care as it is somewhat fragile, but with intelligent treatment does good work.

The fall or inclination of the tables, both copper and blanket strakes, is also regulated by the class of ore.  If it should be heavy then the fall must be steeper.  A fair average drop is 3/4 inch to the foot.  Be careful that your copper tables are thoroughly water-tight, for remember you are dealing with a very volatile metal, quicksilver; and where water will percolate mercury will penetrate.

The blanket tables are simply a continuation of the mercury tables, but covered with strips of coarse blanket, green baize, or other flocculent material, intended to arrest the heavier metallic particles which, owing to their refractory nature, have not been amalgamated.

The blanket table is, however, a very unsatisfactory concentrator at best, and is giving place to mechanical concentrators of various descriptions.

An ancient Egyptian gold washing table was used by the Egyptians in treating the gold ores of Lower Egypt.  The ore was first ground, it is likely by means of some description of stone arrasts and then passed over the sloping table with water, the gold being retained in the riffles.  In these the material would probably be mechanically agitated.  Although for its era ingenious it will be plain to practical men that if the gold were fine the process would be very ineffective.  Possibly, but of this I have no evidence, mercury was used to retain the gold on the riffles, as previously stated.  This method of saving the precious metal was known to the ancients.