26S 



HARD AND WHITE COPPER^ 



Its aAion on 

 poliihed iron. 



Is more fuflble 

 than copper. 



Does not quit 

 the phofphorus 

 without diffi- 

 culty. 



Refcmblcs fteel 

 in hardnefS) 

 grain and colour, 

 and does not tar- 

 nifh by expo- 

 furc to the air. 



A fmall quan- 

 tity of charcoal 

 to be ufed in its 

 preplration. 



Ked enamel. 



Copper and 

 phofphorus can 

 only be com- 

 bined in the dry 

 way. 



ftate of a red enamel, in the form of a grey and brilliant but- 

 ton : on weighing it, it is found to have acquired one twelfth 

 by this operation. 



If the melted phofphorated copper falls on a plate of poliihed 

 iron, it fpreads itfelf in the form of plates of various configu- 

 rations which are iridefcent like the neck of a pigeon. 



Phofphorated copper is much more fufible than red copper : 

 it may be often melted under charcoal powder without lofing 

 its properties. 



The fame phofphorated copper, expofed for a long time 

 under a muffle, does not feparate from the phofphorus with- 

 out great difficulty. 



The copper thus combined with the phofphorus acquires the 

 hardnefs of fteel, of which it has the grain and the colour; 

 like it, it is fufceptible of the moft beautiful polirti; it is turned 

 eafily in the lathe; it does not change in the air: I have for 

 fifteen years, kept buttons of poliflied phofphorated copper in 

 my laboratory, which have not experienced the leaft change. 

 The copper does not develope any fmell on being rubbed : if 

 it was dudile it would be of the greateft utility, lince fat bo- 

 dies do not feem to make any impreffion upon it. 



In the phofphoration of copper there is only a part of the 

 animal glafs decompofed : becaufe a fufficient quantity of char- 

 coal is not employed to convert all the acid into phofphorus; 

 but it is necefTary that this fliould be the cafe, that the phof- 

 phorated copper may feparate and colled with facility. 



The deep red enamel which is formed in this experiment 

 may be advantageoufly employed for porcelain or the enamels, 

 fince it does not change colour in the fire. 



Copper cannot combine with phofphorus except in the dry 

 way. If a cylinder of phofphorus is put into a folution of ni- 

 trate of copper diluted with four or five thoufand parts of wa- 

 ter, at the end of eight days the copper will be found in a me- 

 tallic form, cryftallized and duflile, forming a cafe for the cy- 

 linder of phofphorus. 



pbjervations 



