188 



KEPOET 1892. 



The following is an outline of the methods adopted by Mi*. Pattinson : — 



Carbon. — The sample was dissolved in a solution of double chloride of 

 copper and ammonium, filtered through asbestos, and the residue well 

 washed and burnt in oxygen. The double chloride used was proved to be 

 free from carbonaceous matter. 



Silicon. — The sample was dissolved in hydrochloric acid, evaporated 

 to dryness, and the residue dissolved in hydrochloric acid and hot water. 

 After filtration and washing, the silica was ignited and weighed ; its 

 purity was tested by treatment with hydrofluoric acid and due allowance 

 made for any residue. 



Sulphur. — 1. The sample was dissolved in hydrochloric acid and the 

 evolved gases passed into an ammoniacal solution of cadmium chloride. 

 The precipitated cadmium sulphide was dissolved in the beaker by the 

 addition of bromine water and acidification with hydrochloric acid, and 

 the sulphur precipitated as BaSO^. 



2. The drillings were dissolved in nitric acid, and the solution evapo- 

 rated to dryness with addition of hydrochloric acid, redissolved in hydro- 

 chloric acid and water, filtered, and the sulphur precipitated as BaS04. 



Manganese. — 1. Estimated gravimetrically by the ammonium acetate 

 and bromine process. The precipitate after ignition was weighed as 

 Mn304, and the impurities carried down with the precipitate were deter- 

 mined, and the necessary correction made. 



2. Also estimated volumetrically by the process described by Mr. 

 Pattinson ('Trans. Ohem. Soc.,' 1879, p. 366). 



Fliospliorus. — The sample was dissolved in nitric acid and evaporated 

 to dryness after the addition of hydrochloric acid. The residue was 

 redissolved in hydrochloric acid, filtered, and the filtrate treated with 

 metallic zinc, free from phosphorus, in order to eliminate arsenic and 

 reduce the iron to the ferrous condition. The solution was then boiled, 

 a few drops of ferric chloride added, and the phosphorus precipitated in 

 combination with iron by addition of ammonia and acetate of ammonia. 

 The precipitate was separated by filtration, dissolved in nitric acid, the 

 phosphorus precipitated by ammonium molybdate and weighed as 

 ammonium phospho-molybdate. 



The analytical results obtained by Mr. E. Riley are as follows : — 



The following is a brief outline of the methods of analysis adopted by 

 Mr. Riley in these determinations : — 



Carhon. — By solution of the sample in sodium copper chloride and 



