384 TRANSACTIONS OF SOCIETIES. 



been general or only those of certain commodities ; whether there has 

 been a real or only an apparent expansion of gold production ; and, 

 whether the production is not even now barely sufficient for the world's 

 needs and threatens to become exhausted and so seriously endanger 

 civilisation. 



South African Society of Civil Engineers. — Wednesday, May 14th : 

 F. E. Kanthack, M.I.C.E., President, in the chair. — " The Potchefstroom 

 Reservoir": M. R. Collins. The reservoir was constructed in order 

 to relieve a shortage of water in the Mooi River, and also to provide 

 work for white people. The catchment area was 1450 sq. miles, with an 

 estimated yield of 187 million cubic feet of water per annum. The 

 estimated cost of the work was £20,000. In this connection the subject of 

 unskilled white labour and the system of payments adopted was briefly 

 discussed. 



