150 MEMOIR OF DE. DALTON, AND 



" In order to examine into the power of different solvents, 

 we precipitated with copper a hundredweight of silver, which 

 was dissolved in vitriolic acid, but there were only 30 lbs. of 

 copper used. This, then, enables us, to some extent, to 

 measure the great avidity with which nitric acid seizes on 

 phlogiston, so much excelling the vitriolic acid." 



The amount of each metal needed to precipitate 100 lbs. of 

 silver, is given with the experiments, but to save room, I add 

 a list. 



"135 tbs. Mercury dissolve 100 lbs. of Silver. 



234 „ Lead ditto. 



♦ 31 „ Copper (with nitric acid) ditto. 



30 „ (with vitriolic acid) ditto. 



29 „ Iron (with vitriolic acid) ditto, 



88? „ Tin ditto. 



Bismuth could scarcely be determined. 



64 „ Nickel ditto. 



92 „ Arsenic ditto. 



37 „ Cobalt ditto. 



55 „ Zinc ditto. 



83 „ Antimony ditto. 



51 „ Manganese ditto. 



Amounts of zinc used to precipitate 100 lbs. of metals. 



217 tbs. Zinc precipitated 100 lbs. of pure Gold. 



416 „ „ ditto Platina. 



44 ,, „ ditto Mercury. 



26 „ „ ditto Lead. 



164 „ „ ditto Copper. 



68 „ „ ditto Tin. 



49 ,, „ ditto Bismuth. 



70 „ (the solution was difficult) ditto Antimony. 



Scarcely any precipitation appears with Iron." 



Then, at p. 150, there are certain corollaries, of which the 

 following sentences suit best the subject in hand : — 



COROLLARIES. 



*' A. That dephlogisticated metals unite with different acids 

 in a variable manner (t. e., that different amounts of metal unite 

 to different acids). Thus, 100 parts of silver, dissolved in 



