1 7 ^ Compstiiidt ef Fixed Oil ani MetalUe- Cakes. 



When a mixture of the folutions of foap and corrofive fublimate was made, the fluid aw 

 fumed the appearance of milk, but foon after exliiblted fmall coagula. I: is ahiioft im, 

 pofTibie to filter this liijuor, but the gvcateft part of the mercurial combination is flowly 

 dcpofitcd. This depofition may he accelerated by means of fpiric of wine. The fame 

 combination may be much morcreadiiy etrccled with tlie nitrous folution of mercury ». 



Tlie olc o-mcrcuri;il combination is vifcid, dries dilTicuItly, diflblvcs very well in oil, auu 

 very fparingly in fpirit of wine, h lofes its white colour by expofurc to the air, and ac- 

 <juires a flate colour, which gradually becomes deeper, more efpecially if it be expofed to 

 the fun or any other heat. It readily becomes foft and fluid. It mull be dillinguiflied 

 from tlie mercurial ointment ufed in medicine, for in this the mercury poficfTes the me- 

 tallic (late ; whereas, in our combination, the mercury is in the (late of calx, and fornis^ 

 with the oil a true combination, which perhaps might prove ufcful in medicine. 



The combination of oil and zinc, which I made by means of white copperas, is of a white 

 colour inclining to yellow. It dries fpeedily, and becomes friable. The combination of 

 cobalt and oil, made by means of the folution of regulus of cobalt in aqua fortis, is of a dull 

 leaden colour, and dries with difficulty, though its parts are not conneftcd together. To- 

 wards the end of the precipitation fom° coagula of a green colour, and much more confincnr, 

 fell down. I apprehend that this was a combination of oil and nickel ; for it is known th.iL 

 this femi-metal is almoft always contained in the regulus of cobalt, and that it forms green 

 folutions with acids, while thofe of cobalt are red. I could not ellablifli my conje£lure, 

 bccaufe I was unable to procure nickel. But if it (hould prove well founded, this proccfs 

 will afford an eafy method of feparating the two metallic fubftances. 



I made the combination of oil and tin by means of tlie folution of this metal in aqua-. 

 tegia. It is white, not fufible when expofed to heat, like all the other oleo-metallic com- 

 binations ; but it is decompofed without any change in the form of its parts. I attribute 

 this circumflance to the great quantity of metal contained in this combination, as we 

 Ihall fee. 



The oleo-martial combination is of a reddifh brown colour, tenacious, and eafily fufibic. . 

 When fpread upon wood it foaks in and dries. It is eafily foluble in oil, more particularly 

 oil of turpentine, to which it gives a good colour, which may prove ufeful as a varnifh. 



The oleo-cupreous combination which I have made by means of blue vitriol, is refinous 

 to the touch while moid, is of a green colour, and becomes dry and brittle. When di- 

 gefted in fpirit of wine its colour becomes deeper, and it liquefies, but does not ditfolve in 

 the cold. Ether renders its colour deeper and more beautiful, inftantly liquefies it, and 

 difTolves a confiderable quantity. This combination is abundantly foluble in oils, to which, 

 it communicates a pleafant green colour. 



The combination of oil and lead, made by means of the folution of fugar of lead, is 

 white, tenacious, and very adhcfive when heated. The union of oil and the lead is not 

 fo intimate in the diachylon {or diredl folution of litharge in oil) as in this combination ; 

 for this lad, when fufed, is tranfparent, and becomes rather yellowifli if the heat be fome- 

 what increafed ; but the diachylon is opake, and the oil which enters into its compofition , 



* Probably with different cffcfts, accordingly as the folution, fuppofcd to be faturatcd, is made with or without 

 heat. N. 



has 



