ISO MEDICINAL PREPARATIONS OF GOLD. 



slate of minute division, oxide of gold precipitated by 

 potash, the oxide precipitated by tin, and the triple 

 muriate of gold aud soda. These he considers as superior 

 to mercurials. Some experiments by Mr. Vauquelia 

 on the preparations of gold thus introduced into notice, 

 have already been given*, and we shall now present our 

 readers with some remarks on the subject by the gentlemen 

 above mentioned, one of whom enjoyed the advantage 

 of a personal acquaintance with Dr. Chrestien, at Mont- 

 pel lie r. 

 Gold in pow- The first preparation of gold employed by this physician 

 "*r- r * , was the metal in a state of minute division. To obtain this; 



How prepared . , , . . 



by Dr. Cures- he formed an amaigam, by triturating leaf gold with seven 



* iaa « times its weight of mercury in a marble morlar with a glass 



pestle, and then expelling the mercury by means of a pow- 

 erful lens in the height of summer, or dissolving it out by 

 pure nitric acid. 

 Another mode The present writers recommend rather to precipitate a 

 wcoameuded. so l u tion of muriate of gold by a solution of sulphate of 

 iron at a minimum, filtering, and washing the precipitate 

 with water acidulated by muriatic acid, in order to dissolve 

 out the oxide of iron mingled with the precipitated gold. - 

 When the gold is thoroughly dried, it is in the state of a 

 • deep brown powder, though in the metallic state; all metals 



losing their brilliancy by being minutely divided. 

 Sokvtlonof To prepare the oxide of gold precipitated by potash, 



£ f,lcl they direct one part of nitric acid at 40° [sp. gr. I*3y6] 



to be mixed with four of muriatic acid at 12° [1*089]; and 

 cupelled gold to'be heated with eight times its weight of 

 this menstruum in a matrass with a long, narrow neck, 

 till it boils gently. When no more gold will dissolve at 

 this temperature, the solution is to be poured off, and 

 evaporated to dryness in another matrass by a gentle fire. 

 The residuum of this evaporation is to L« dissolved in dis- 

 tilled water, and filtered. 



-. . ,t. The filtered solution is to be treated with potash, to 



. tea ay ) ^ 



ah. ' separate from it the oxide of gold: but in this there are 



great difficulties, and the whole tanuot he thrown down, 

 without part cf it being reduced to the metallic state. 



* Journal, vol. XXX, p. 248. 



The 



