DR. E. FRANKLAND’S RESEARCHES ON ORGANO-METALLIC BODIES. 
267 
should then have the anomaly of the combination of equal volumes of two radicals 
being attended by condensation. The determination of the specific gravity of zinc- 
ethyl vapour supplies us with the first datum respecting the vapour volumes of the 
class of metals to which zinc belongs. It has hitherto been assumed, that the vapour 
volume of these metals is equal to that of hydrogen ; but the vapour volume of zinc- 
ethyl goes far to contradict this assumption. 
Although zincethyl is remarkable for the intense energy of its affinities, which place 
it nearly at the head of the list of electro-positive bodies, yet it does not appear to be 
capable of forming any true compounds with electro-negative elements, its reactions 
being all double decompositions in which the constituents of the zincethyl separate. 
When a few drops of zincethyl, diluted with ether to prevent inflammation, are passed 
into a mercurial eudiometer containing dry atmospheric air, a rapid absorption of 
oxygen takes place, with the formation of a white amorphous solid composed of 
zinc, ethyl, and oxygen. This reaction, which is also common to zincmethyl and 
zincamyl, led me to suppose, that, like cacodyl, these bodies combined directly with 
oxygen*; but the results of the action of oxygen upon zincethyl detailed below, prove 
that no such compound is formed ; the white body being ethylate of zinc, and not an 
organo-metallic compound, in the strict sense of the term. 
Action of Oxygen upon Zincethyl. 
When zincethyl is brought into contact with oxygen or atmospheric air, it instantly 
ignites, burning with a brilliant blue flame, fringed with green, and evolving dense 
clouds of oxide of zinc ; a cold body held in this flame, becomes coated with a black 
deposit of metallic zinc, surrounded by a white ring of oxide of zinc. In this rapid 
action of oxygen, all the elements of zincethyl are attacked, and the products are 
oxide of zinc, water, and carbonic acid ; but if the zincethyl be placed in a vessel 
filled with dry carbonic acid and immersed in a freezing mixture, oxygen gas may be 
slowly admitted without inflammation taking place. At first the absorption of oxygen 
is rapid and attended with the production of white fumes, which fall to the bottom of 
the vessel in the form of a white powder ; but the action soon becomes greatly re- 
tarded, owing to the formation of a solid crust upon the surface of the zincethyl, pro- 
teeting the latter from further contact with oxygen, so that after the lapse of weeks, 
or even months, the oxidation is very imperfect. During the progress of the oxida- 
tion, a small quantity of a blaek substance, resembling finely-divided metallic zinc, 
is deposited from the liquid ; but the amount of this deposit is so small, that I did not 
succeed in obtaining more positive evidence of its nature. 
As this mode of oxidizing zincethyl in a pure state was found to be incapable of 
yielding results from which the nature of the action could be readily deduced, it was 
modified by mixing the zincethyl with about three times its bulk of anhydrous ether, 
and then submitting it, as before, to a slow current of oxygen. At first the absorp- 
* Philosophical Transactions, 1852, p. 431. 
2 o 
MDCCCLV. 
