THE WITWATERSRAND GOLD REGION 749 
permeating through the conglomerates after their formation, in much 
the same manner as gold is deposited in fissures elsewhere. They 
think that with the gold were also deposited the pyrite, marcasite, 
and other secondary minerals found in the deposits, including the 
secondary silica, which has bound the once open pervious conglomer- 
ates into solid compact rocks. Most of the geologists and engineers 
who have been directly connected with the mines in the Witwaters- 
rand district also hold more or less similar beliefs. John Hays Ham- 
mond,’ formerly the noted engineer of the Consolidated Goldfields 
of South Africa, thinks that a large part of the gold got into the con- 
glomerates in this way, but that some of it was also deposited originally 
with the conglomerates. 
W. H. Penning? and L. DeLaunay? have suggested that the 
conglomerates were formed in sea water which was heavily charged 
with gold and iron sulphide in solution, and that these were deposited 
in the conglomerates during their formation. ‘This theory has not 
received much support from others familiar with the region. 
t “The Genesis of the Witwatersrand Banket,”’ being chap. vi of The Witwaters- 
rand Goldfields, Banket and Mining Practice, 1898, by S. J. Truscott. 
2 Jour. Soc. Aris, London, Vol. XXXVI, 1888, p. 437. 
3 Les mines d’or du Transvaal, 1896. 
