PRECrPITATION OF OXIDES BY THEIR OWN METALS. ^ | 



examining-, whether other metals were capable of ftjnnm^ 

 similar chains with their solutions and v/ater. 1 communi- 

 cate these experiments, because I know of no one except 

 Ritter, who has attended to these chains, and thej' have 

 appeared to me interesting- with respect to tlie particular 

 circumstances accompanying them, though they are all 

 founded on the same system. 



Experiments with solutions of copper, another Jluid, and 

 copper. 



i. Into a cylindrical glass I poured a solution of half an Experiniraa 



wi.li civstaJ- 



li ed g.-c'eii 



ounce of crystallized green muriate of copper in twoouiices 

 of water, and added with the greatest cawtiun three ounces ;..ii,iiateal£ai»- 

 of distilled water, so that the liquors remained separate, '''^"• 

 one above the other. I then immersed in the two liquors a. 

 slip of polished copper, half an inch broad and six inches 

 long, whi-ch rested on the bottom of the gl«ss. At tlie ex- 

 piration of two hours no actioa appeared to have t^ken 

 place, except that the slip of copper was covered wuh a 

 white crust, that continued increasing for twelve hoursl Oa 

 examining this substance, it was found to be wljite muri- 

 ate of copper, formed by the oxide of the green muriate 

 sharing its oxigen with the metallic copper iui.nereed in the 

 liquor. 



2. As the preceding experiment iiad bhown, thtit the Y.yn. ifrvh 

 green muriate of copper could not form a chain capable of ^^*i'^^ :.'.unuie 

 reducing completely the oxide of copper held in solution, "^ ^ '' " ' 

 1 was desirous of seeing whether the white mnriate woald 

 comport itself differently. Accordingly I boiled a drachm 

 of this salt with thi-ee ounces of water for a quarter of aa 

 hour, filtered it when cold, and placed the solution iji con- 

 tact with two ounces of distilled water and a slip of po- 

 lished coppt r as in the preceding- experiment. Having ob- 

 tained no precipitate of copper at the expiration of a few 

 hours, or even in some days, I aircribe this nullity of efrect 

 to the little diiierence between the specilic gravity of the 

 two fluids; for it is well knowi), that water clisvolves very 

 iittle white muriate of copp<;r; v. hence the two iluids wiit 

 nriite immediately anddtbtsoy the ciiain. 



3. Half 



