The auriferous clays of the Gold Coast are thinly covered with humus, and are not buried, as in Australia, by ten to thirty feet of unproductive top-drift. The whole, therefore, can be run through the sluices before we begin mining the underlying strata. Washing will be easier during the Rains, when the dirt is looser; in the Dries hard and compact stuff must be loosened by the pick and spade or by blasting. There will not be much loss by float-gold, flour-gold, or paint-gold, the latter thus called because it is so fine as to resemble gilding. Spangles and specks are found; but the greater part of the dust is granular, increasing to 'shotty gold.' The natives divide the noble ore into 'dust-gold' and 'mountain-gold.' The latter would consist of nuggets, 'lobs,' or pepites, and of crystals varying in size from a pin's head to a pea. The form is a cube modified to an octahedron and a rhombic dodecahedron. These rich finds are usually the produce of pockets or 'jewellers' shops.' I am not aware if there be any truth in the rule generally accepted: 'The forms of gold are found to differ according to the nature of the underlying rock: if it is slate the grains are cubical; if granite they are flat plates and scales.' And, lastly, the sluice begat the jet, or hydraulicking proper, which is at present the highest effort of placer-mining. We thus reverse the primitive process which carried the wash-dirt to the water; we now carry the water to the wash-dirt. In California I found the miners washing down loose sandstones and hillocks of clay, passing the stuff through sluices, and making money when the gold averaged only 9_d_. and even 4_d_. to the ton. A man could work under favourable circumstances twenty to thirty tons a day. An Australian company, mentioned by Mr. R. Brough Smyth, with 200 inches of water, directed by ten hands, 'hydraulicked' in six days 224,000 cubic feet of dirt. The results greatly vary; in some places a man will remove 200 cubic yards a day, and in others only 50. Hydraulic mining on the Gold Coast, owing to the conformation of the country, will be a far simpler and less expensive process than in California or Australia. In the latter water has first to be bought, and then to be brought in pipes, flumes, leats, or races from a considerable distance, sometimes extending over forty miles. It is necessary to make a reservoir for a fall. The water then rushes through the flexible hose, and is directed by a nozzle against the face of the excavation. The action is that of a fireman playing upon a burning house. Most works on mining insist upon those reservoirs, and never seem to think of washing from below by the force-pump.