ON COATING MFTALS WITH PLATINA. 



293 



may be called jjlatining [platinure], as we say gilding;, sil- 

 vering : the other plating, a term appropriated by custom to 

 a less superticial application, requiring a different process. 



Platining may be executed like gilding, either by the in- Th.it of 

 tervention of mercury, or by means of a solution oi muriate ^^^^^^'''S- 

 of plntina in ether. 



1. I long ago made known the possibility of forming an By means of 

 amalgam of platina, and described the processes for obtain- a">'i'8^"i- 

 ing it*. Mr. Proust, in a letter addressed to Mr. Vau- j^^^'^™ 

 quelin, inserted In the Ann. de Chim. 'fjluviose, an. 12 Proiut, 

 [February, 1804], bus said, that " hot mercury poured on 

 the spongy substance remaining after the calcination of 

 aramoniacal muriate of platina, dissolves it perfectly ; and 

 the result is a fatty amalgam, that does not grow hard by 

 l<eeping, and spreads well on copper, gold, or silver; so 

 that it might facilitate the plating of the former." 



From the note following this passage it appears, that fourcroy and 

 Messrs. Fourcroy ■and Vautjuelin also accomplished this Vauquelm, 

 anialgamation b\^ the same process; that they even effected 

 it without heat, and that, after having remained fluid for 

 sometime, it became very solid; an effect that might be 

 accelerated by the application of a gentle heat. 



Lastly, Mr. Hatchett published in Nicholson's Journal and Count 

 for October, 1804, a Letter, in which Count Mussin p^^^^'jJJJ.^^ 

 Poushkiu gave him the particulars of the processes of amal- 

 gamation, by means of which he rendered platina perfectly 

 malleable. 



At present therefore we cannot question the union of 

 platina with mercury by means of simple processes, not 

 expensive, and producing a suitable consistency for a solid 

 application of the fixed metal :'but it does not appear, that 

 the processes of this new art have hitherto been published 

 [in France] with any details; I shall therefore make known 

 those described by Mr. Trommsdorff in the 7th vol. of his 

 Journal, from the communication of Mr. Straussf. 

 ****** 



* Ann. deChim. January 1798, vol. XXV, p, 14, andfol. 

 •f See also Nicholson's Journal, vol. IX. [As the account that fol- 

 lows in the text is the same with that uiven at p. SO 3 of the vol. of the 

 Journal quoted by Mr, Guy ton-Morveau, it is omitted here as unne- 

 . pei?4[y. C.] 



