386 TRANSACTIONS OF SOCIETIES. 



parent, the immune character can be combined with ahnost any 

 other desirable characters existing in a susceptible wheat, and 

 the type thus built up may be " strengthened " by the aid of 

 crossing with a " strong " parent. Similar experimental 

 breedings have been carried out with other plants. 



TRANSACTIONS OF SOCIETIES. 



South African Institution of Engineers.— Saturday, March gth : 

 Mr F H Davis, President in the chair.— " Loss due to impact in Call - 

 fornian stamps": A. S. Ostreicher. The author had investigated the 

 impact between cam and tappet by the work due to deformation. Equa- 

 tions were given for determining the limiting values of percentage loss. 



Chemical Metallurgical, and Mining Society of South Africa.— 

 Saturdav, March i6th : Mr. W. R. Dowling, M.I.M.M., Vice-President, 

 in the "chair.— "The Luminator purification treatment of water for 

 .'^teani boilers": W. Cullen. The treatment consists in running the 

 water over aluminium plates under certain conditions. This prevents 

 scaling and loosens anv scale previously formed. The author had tried 

 the method for fifteen months with two 25 h.p. boilers, using about 3,000 

 gallons of water per twenty-four hours, and characterised the improve- 

 ment noticed at first as remarkable and striking, though subsequently 

 it was less marked. Before the application of the aluminium launders ■ 

 so mucli adherent scale used to be formed that the boilers needed 

 cleaning every three or four weeks. The first result of this treatment- 

 was to loosen what scale there had been formed and render it capable 

 of being blown off. The scale subsequently formed was much less than 

 usual and easily removable. The author was unable to explain the under- 

 lying principle. 



Geological Society of South Africa.— Monday, March iSth : Mr. 

 H. S. Harger, President, in the chair.— "The Palabora plutonic complex 

 of the Low countrv, and its relationship to the pegmatites of the 

 Leydsdorp mica fields :" A. L. Hall. A considerable area, south of the 

 Murchison Range, is covered by a group of plutonic rocks intrusive into 

 the older granite. This group— the Palabora plutonic complex— is made 

 up of a genetically connected series of massive granites, syenites, and 

 pyroxenites. Its age cannot be definitely fixed, but its intrusion probably 

 belongs to a period intermediate between the older granite and the 

 Bushveld igneous rock^. A large number of coarse quartz-albite- 

 pegmatites are associated with the margin of the complex, and probably 

 represent its residual motherliquor, but have no connection with tJie 

 older granite. — " The crystalline metamorphic limestone of Lulukop, and 

 its relationship to the Palabora plutonic complex:" A. L. Hall. The 



intrus ion of the Palabora complex was accompanied by pronounced 

 contact metamorphism, particularly on the limestone of Lulukop. The 

 latter, especially at the Guide Copper Mine, contains admixtures of 

 igneous material, represented by pyroxene and orthoclase. A_ large mass 

 of th? limestone had evidently been caught up by the ipvading magma 

 and intensely altered. 



Institution of Electrical Engineers. — Wednesday, .\pril loth : Mr. 

 W. F. Long. President of local section, in the chair. — Presidential 

 address: W.F. Long. A review was given of the electrical industry in 

 the Cape Peninsula s:nce its inception in 1882, by a private company, 

 which was bought up In' the Table Bay Harbour Board in 1886. The 

 Harbour Board then took over the lighting of the Houses of Parliament, 

 the electricity for which had been supplied since 1885 by a special steam 

 driven generator. The Harbour Board plant also supplied the Cape 

 Town Railway Station with energy until 1889. when the Railway Elec- 

 trical Department was inaugurated, electrical train lighting being then for 



