Occurrence of the Element Gallium in Clay-Ironstone. 35 



There is still evidence of liquation of gold towards the centre, but 

 comparison of fig. 12 with those which immediately precede it' will 

 show how greatly the arrangement of the alloy has been modified by 

 the presence of the additional 8 per cent, of silver. The proportion 

 of silver in this alloy was proved by assay to be 15'5 per cent. 



As there was still evidence of liquation, the metal was cast with 

 .still more silver, making 20 per cent, of silver in all. The alloy, 

 when cast into a mould, proved to be almost uniform in composition] 

 the difference between the centre and the extreme portions being very 

 slight. 



Liquation had practically ceased, a fact which proves incontest- 

 ably that silver is the solvent for the base metals, zinc and lead, 

 when they are alloyed with gold. 



Conclusions. (1) Alloys of gold with base metals, notably with 

 lead and zinc, now largely often met with in industry, have 

 the gold concentrated towards the centre and lower portions, which 

 renders it impossible to ascertain their true value with even an 

 approximation to accuracy. 



(2) When silver is also present these irregularities are greatly 

 modified. 



The method of obtaining "cooling-curves" of the alloys shows 

 that the freezing points are very different when silver is present and 

 when it is absent from the alloy. 



(3) This fact naturally leads to the belief that if the base metal 

 present does not exceed 30 per cent., silver will dissolve it and form 

 a uniform alloy with gold. 



(4) This conclusion is sustained by the experiments illustrated by 

 figs. 9, 10, 11, 12, which, in fact, gradually lead up to it, and enable 

 a question of much interest to be solved. 



41 Ori the Occurrence of the Element Gallium in the Clay- 

 Ironstone of the Cleveland District of Yorkshire. Prelimi- 

 nary Notice." By W. N. HARTLEY, F.R.S., Professor of 

 Chemistry, and HUGH RAM AGE, A.R.C.S.I., F.I.C., Assistant 

 Chemist in the Royal College of Science, Dublin. Received 

 April 13, Read May 7, 1896. 



In the course of an investigation of flame spectra at high tempera- 

 tures ( Phil. Trans.,' A, vol. 185, pp. 10291091 (1894) ) extended to 

 the basic Bessemer process, the authors were occupied last July and 

 August in observing the flames from the converters at the North 

 Eastern Steel Company's Works, at. Middlesbrough-on-Tees. A 

 large number of photographs were taken in series during the pro- 

 gress of the "blow," and also of the "after blow," but these will 



D 2 



