142 ELECTROLYSIS. 



CHAPTER IX. 



SILVEE AND GOLD PLATING. 



Importance of Silver-plating as an Industry Composition of Silver Baths 

 Concentration of Baths Anodes Preparation of Articles for Silver-plating 

 Conduct of the Operation Polishing of the Pieces Observations relating 

 to Organic Matters Oxidised or Antique Silver Weakened Solutions 

 Silver-plating by simple Immersion Composition of Baths for Gold- 

 plating Preparation of Articles for Gold-plating Description of the 

 Process Colouring of the Gilt Articles Variety of Colours of the Gold 

 Depositions Incrustations of Gold and Silver Weakened Solutions 

 Gilding by Single Immersion. 



1. SILVER-PLATING. 



IMPORTANCE OF SILVER-PLATING AS AN INDUSTRY. Silver- 

 plating as industrially applied was invented in 1840 by Richard 

 Elkington, and has long remained a kind of monopoly in the 

 hands of a very few firms, at the head of which can be cited 

 the names of Messrs. Elkington in England, and Messrs. 

 Christofle and Co. in France. The majority of patents have 

 lapsed twenty years since, and the number of manufacturers 

 has naturally been increasing, but not to any considerable extent, 

 as the important capital required by the high value of the 

 metal, has been a bar to many would-be manufacturers. 

 There are not more than ten factories in Paris where the silver- 

 plating business is conducted on a really industrial footing. 

 The small installations do not succeed, encumbered as they are 

 with general expenditure which prevents them advantageously 

 competing with more powerful and better organised firms. 



The nickel-plating industry is, on the contrary, greatly 

 practised, not only by the professional nickel-platers, but also in 

 a large number of engineering workshops, where it renders 

 great service, without being expensive to instal. 



