Effects of Animal Chardbdl on SoluViom. 12^ 



Four grains trisacetate of lead ; same results. 

 Four grains tartar emetic in one ounce water, with twenty 

 grains of the prepared charcoal, in the cold ; agitated occasion- 

 ally for several days ; still a copious precipitate, with hydro- 

 sulphuret of ammonia. After a second addition of twenty 

 grains of the charcoal, only a trace of antimony, with sul- 

 phuretted hydrogen. 



Lime-water was deprived entirely of the lime which it con- 

 tains, in the cold, as Dr. Paris previously observed, so that the 

 liquid remaining did not act on reddened litmus. 



Arsenious acid was not taken down entirely in six weeks by 

 great excess of the charcoal, no heat being applied. 



No quantity of the charcoal could take down bisulphate of 

 copper. 



Ammonia was added in excess to bisulphate of copper, so as 

 to form the deep-blue solution of ammonio-sulphate : the latter 

 was readily taken down by the charcoal, and the liquid became 

 perfectly colourless. Strong ammonia was digested in the 

 cold upon the charcoal containing the salt of copper, and also 

 boiled upon it, without dissolving a trace of it, as the ammonia 

 did not become blue even when poured ofif and exposed to the 

 air. In a certain experiment, the deep-blue colour of five 

 grains bisulphate of copper in half an ounce of caustic am- 

 monia, diluted with one and half ounces water, was much 

 impaired by twenty grains of the charcoal. Increasing the char- 

 coal every second day, by five grains at a time, with thirty-five 

 grains, the colour had become very slight, and was entirely 

 destroyed by forty grains -, nor did the supernatant ammonia 

 contain any protoxide of copper. 



Five grains of nitrate of silver, in the same quantity of am- 

 monia and water, with twenty grains of the charcoal. Next 

 day no trace of silver in solution could be detected : two and a 

 half grains nitrate of silver added ; agitated occasionally with 

 the charcoal, but after several days there was still silver in 

 solution. On examining the phial containing the above mate- 

 rials some time afterwards, shining metallic spangles were per- 

 ceived among the charcoal. 



The solution of chloride of silver in ammonia was also taken 

 down completely by the charcoal. 



A solution was made of ten grains hydrated protoxide of lead 



