by South Africa. Department of Mines and Industries

1911

by South Africa. Department of Mines and Industries

1922

by South Africa. Department of Education

2007 · RainbowSA

by South African Institution of Mechanical Engineers

1914

by South African Institution of Engineers

1914

by South African Institution of Engineers

1914

by New South Wales. Parliament

1915

by South African Institute of Mining and Metallurgy

1899

by Chemical, Metallurgical and Mining Society of South Africa, Johannesburg

1919

by South Africa. Dept. of Mines and Industries

1911

by Natal (South Africa). Legislative Assembly

1904

by South African Institute of Race Relations

1972 · Univ of California Press