Miscellanies. 



387 



For univrought silvering, take two parts of silver (precipitated 

 from the nitric solution by copper leaves,) two parts cream of tartar, 

 two parts marine salt well pulverized. Apply this in the same way 

 as above described. When the piece is perfectly whitened, put it 

 into water containing a little potash. Agitate it well in clear water, 

 without which it will tarnish and become yellow. — Jour, de Con. 

 Usuelles. 



13. Glass syphons for transferring corrosive fluids. — M. CoL- 

 LARDEAU has designated the form of a glass syphon, which saves the 

 necessity of applying the mouth or even the finger to either end of 

 the tube. Dip the end a of Fig. 1. into the fluid to be transferred, 

 and pour into the funnel or side opening b. a quantity of the same 

 fluid, until it flows out of the end c. The fluid in the vessel F. G., 

 then rises and continues through a d e c. In this case, the branch 

 m n remains full, while the liquid in 6 n subsides to near the bend n. 



Fiff. 2. 



' The same object is effected by the more simple form of Fig 2., 

 provided the opening c is closed with a finger until the long branch 

 of the syphon is full, — or, the application of the finger is unnecessary 

 if the fluid be poured into the funnel faster than it can be discharged 

 through c. In that case, the long branch of the syphon will fill and 

 then act in the usual way. — Bull. D^Encour. Fev. 1832. 



14. Carbonate of lime and its compounds ; (M. Becq,uerel.) — 

 Calcareous carbonate is found in countries of the oldest formation, 

 where it often forms entire mountains. It is found disposed in beds 

 of a crystalline texture, sometimes saccharoidal, and sometimes more 



