Mr. Buckton on the Mercuric, Stannic, and Plumbic Ethyles. 385 



The presence of iodide of distannic triethyle amongst the stannic 

 bodies in Lowig's experiments can be satisfactorily accounted for by 

 presuming the incomplete reduction of tlie iodides by the alloy of 

 tin and sodium employed in the reactions. 



The behaviour of zincethyle towards the chlorides of tin may be 

 expressed, step by step, by tfie following equations, the tin-salt being 

 supposed to be added to the zincethyle : — 



I. 2ZnC,H-,+ SnCl,=Sn (C\H.)., +2ZnCl 

 II. 3Zn C, H, + 2Sn Cl.,=Sn., (C, H.);Cl + 3Zn CI 



III. ZnC,H,+ SnCl=Sn" C,H. C1+ Zn CI; also 



IV. 2ZnC,H,+ SnCl =SnC,H, + ZnC,H, + ZnCl. 



v J 



Y 



Double compound ? 

 I have failed in satisfactorily separating the radical stannic ethyle 

 from the excess of zincethyle, as represented in the last reaction. By 

 the addition of water great heat is generated, and tin is thrown down 

 in its metallic state. 



By distillation also, the radical stannic ethyle is similarly broken up, 

 2SnC, ir = Sn(C,H,), + Su. 



Plumbic diethijle. 



In the abstract above alluded to, I have stated the difficulties 

 which at that time prevented my obtaining the lead radical in a state 

 of purity. This difficulty arises from its tendency to decompose 

 suddenly at a point below that of ebullition. This disadvantage is 

 entirely obviated by conducting the distillation in vacuo, or at least 

 under reduced atmospheric pressure. The organo-metal was found 

 to distil unchanged under a pressure of 7'o inches of mercury at a 

 temperature of 152° C, the barometer at 30"5 inches. This is a 

 remarkable lowering of the boiling-point, which at ordinary atmo- 

 spheric pressures appears to be a few degrees above 200° C. 



Analysis gave numbers leading to the formula 

 Pb C, H,„ or Pb (C, Hj),. 



Plumbic diethyle is a limpid and colourless fluid, possessing a 

 specific gravity of 1-G2. It burns with an orange flame, tinged at 

 the edges with pale green, and disengages whilst burning much oxide 

 of lead. 



The only salts hitherto prepared from this radical seemed formed 

 on the ty])e of the sesquioxides. By passing excess of hydrochloric- 

 acid gas over the organo-metal, hydride of ethyle is liberated, and 

 chloride of diplumbic triethyle is obtained. 



2 Pb (C, II,),-f II Cl=Pb, (C, II,)3 Cl-FC, II, H. 

 The chloride is a fine crystalline body, occurring in long needles, 

 which fuse at a gentle heat, and then take fire, with the character- 

 istic lead flame. 



Oxide of diplumbic triethyle may be obtained by heating any of the 

 corresponding salts with strong potash, or by acting on a solution of 

 the chloride witii oxide of silver. It is a crystalline body, which 

 fuses into an oil-like litjuid, at a gentle heat. 



Sulphuric acid forms an abundant crop of asbestos-like needles 

 Phil. Ma,). S. 4. Vol. 18. No. 121. Nov. 1859, 2 C 



