250 Dr. E. Frankland on a New Series of 



when exposed in considerable quantity. When allowed to absorb 

 oxygen slowly, it forms a white amorphous oxide ; it combines 

 also directly with iodine, chlorine and bromine. In contact with 

 water it is instantaneously decomposed into oxide of zinc and 

 hydride of sethyle, 



C4H5Zn\_ rC4H5,H 

 HO J-\ ZnO. 



Its formula must therefore be C"* H* Zn. I reserve for a 

 future communication the complete history of this and the fol- 

 lowing compound. 



Zincamylium. — This body is generated when iodide of amyle 

 is decomposed by zinc at the temperature of 180° C. It is a 

 colourless and transparent liquid which emits white fumes in 

 contact with the air, but does not spontaneously inflame ; it is 

 decomposed in contact with water into oxide of zinc and hydride 

 of amyle, 



CinpiZn\__JCiOH"H 

 HO J - L ZnO. 

 From this circumstance, and its analogy with zincmethylium, 

 there can be no doubt that its formula is C^® H^^ Zn. 



Action of Mercury upon Iodide of Methyle in presence of Light, 



When iodide of methyle is exposed to sunlight in contact with 

 metallic mercury, it soon becomes coloured red from the separa- 

 tion of free iodine ; after several hours' exposure this coloration 

 disappears, and a small quantity of the yellow iodide of mercury 

 subsides to the bottom of the liquid : after the action of sunhght 

 for several days, the bulk of the mercury is observed to have 

 considerably diminished, and white crystals begin to be deposited 

 around the sides of the glass vessel : finally, after about a week's 

 exposure, the liquid solidifies to a colourless crystalline mass : 

 when this is digested with aether, the new compound dissolves, 

 and is thus separated from metallic mercury, and from the small 

 portion of iodide of mercury which is collaterally formed. Only 

 a very small quantity of gas is evolved during the formation of 

 the white crystalline compound. By spontaneous evaporation 

 the sethereal solution solidifies to a mass of minute colourless 

 crystalline scales : these, dried in vacuo and submitted to ana- 

 lysis, yielded the following numbers : — 



I. '3170 grm. dissolved in alcohol and treated with nitrate of 

 silver, gate '2142 grm. iodide of silver. 



II. -6205 grm. burnt with oxide of copper, gave '0813 grm. 

 carbonic acid, '0505 grm. water, and '5960 grm. protoiodide 

 of mercury. The iodide of mercury, a small portion of which 

 was decomposed into metallic mercury and periodide, collected 



