404 Prof. W. N. Hartley and Mr. H. Ramage. 



gallium, &c., precipitaied, after reducing the iron to the ferrous 

 state. First precipitate, U. The second contained some gallium ; 

 the third, very dark in colour, was free from that metal. 



The precipitates P, R, and U were dissolved in hydrochloric acid , 

 and the solutions filtered to remove a small quantity of insoluble 

 matter which was added to residue M. Two drops of violet-coloured 

 filtrate were tested with potassium ferrocjanide, and so marked was 

 the reaction that it was decided to repeat the process of reduction and 

 precipitation to remove as much iron as possible. The first precipitate 

 W contained nearly all the gallium ; the second contained a small 

 quantity, and the third contained none. 



The first and second precipitations Z7, whose spectra are seen in 

 134 1 and 134 3 , contain a small quantity of gallium. They were redis- 

 solved, reduced, and boiled with excess of ammonium acetate, and the 

 precipitate collected. A second precipitate was free from gallium. 

 The former was fused with caustic soda, extracted with water and 

 filtered. The filtrate was acidified wihh hydrochloric acid, and boiled 

 with ammonia for some time, and the gallium phosphate thus pre- 

 cipitated was collected. This precipitate was added to W. 



Residue W, Sfc. This contained principally gallium and chromium 

 phosphate with some iron phosphate. It was dissolved in hydro- 

 chloric acid, and the solution made to contain about one-fourth its 

 volume of strong hydrochloric acid. Potassium ferrocyanide was 

 added, but not an excess, and the bulky precipitate collected. An 

 excess of the reagent was added to the filtrate, which, after standing 

 twenty-four hours, was filtered. Very small quantities of the two 

 precipitates were examined spectrographically ; the second is decidedly 

 richer in gallium than the first. 



Residues M and M' z with the small Residues added to them as 

 described. Ignited at a red heat to burn combustible matter. The 

 mass became grey and weighed, when cold, 8 grams. It was very 

 bulky, and consisted largely of silica. Fusion with fusion mixtures 

 converted the silica into alkaline silicates, which were removed by 

 solution in water, leaving a black residue. This was fused with 

 caustic soda and sufficient nitre to oxidise the graphite, &c. Water 

 dissolved all of this, excepting a small quantity of red oxide of iron, 

 part of which was examined for gallium. None present. 



The filtrate was acidified with hydrochloric acid, evaporated to 

 dry ness, and dried at 120 C. to dehydrate silicic acid. 



The dry residue was digested with strong hydrochloric acid, and 

 water added. It was then filtered to remove some silica, which was 

 found to have retained only a trace of gallium. 



The filtrate was mixed with a small excess of ammonia, and boiled 



for some time; the gallium being precipitated probably as phosphate. 



The filtrate in this and in all similar cases was again boiled, after 



