1888.] Properties of Metals and the Periodic Law. 425 



March 15, 1888. 



Professor G. G. STOKES, D.C.L., President, in the Chair. 



The Presents received were laid on the table, and thanks ordered 

 for them. 



Professor Oliver Joseph Lodge (elected 1887) was admitted into 

 the Society. 



The following Papers were read :— ■ 



I. " On certain Mechanical Properties of Metals, considered in 

 Relation to the Periodic Law." By W. Chandler RobeRts- 

 Austen, F.R.S., Professor of Metallurgy, Normal School of 

 Science, and Royal School of Mines, South Kensington. 

 Received March 15, 1888. 



(Abstract.) 



The author points to the great industrial importance of the in- 

 fluence exerted by small quantities of metallic and other impurities 

 on masses of metals in which they are hidden. He states that this is 

 most marked in the case of iron, and that when Bergman discovered, 

 in 1781, that the difference between w r rought iron, steel, and cast 

 iron depends on the presence or absence of a small amount of 

 41 graphite," he was astonished at the smallness of the amount of 

 matter which is capable of producing such singular changes in the 

 properties of iron. The evidence as to the importance of small 

 quantities of impurity is quite as strong in other directions at the 

 present day, as is shown by the statement of Sir Hussey Vivian, that 

 one-thousandth part of antimony converts " best select " copper into 

 the worst conceivable, and by the assertion of Mr. Preece, that " a 

 submarine cable made of the copper of to-day," now that the neces- 

 sity for employing pure copper is recognised, " will carry double the 

 number of messages that a similar cable of copper would in 1858," 

 when the influence of impurities in increasing the electrical resistance 

 of copper was not understood. 



Allusion is made to the effect of a small quantity of tellurium on 

 bismuth. Commercially pure bismuth has a fracture showing brilliant 

 mirror-like planes, but if one-thousandth part of tellurium be present 

 the fracture is minutely crystalline. Specimens of such bismuth 



