DR. E. FEANKLAND’S EESEARCHES ON OROANO-METALLIC BODIES. 413 
A determination of the specific gravity of the vapour of this body gave the following 
results : — 
Weight of substance 
TSOSgrm. 
Observed volume of vapour . . , 
67’0 cub. cent. 
Temperature of oil-bath . . . . 
124°-5 C. 
Height of barometer 
756'0 mm. 
Height of inner column of mercury 
38'0 mm. 
Height of column of oil . 
275’0 mm. 
Specific gravity of vapour .... 
= 3-1215 
This number does not correspond with that which ought to have been obtained with a 
compound of the above formula, unless we adopt the exceedingly improbable assumption 
that it contains two volumes of zincmethyl vapour united with one volume of ether 
vapour without condensation. On the other hand, it accords closely with the specific 
gravity of the vapour of a mixture of zincmethyl and ether in the above proportions, as 
seen from the following calculation : — 
Four volumes of zincmethyl vapour . 
. . . . 6-5672 
Two volumes of ether vapour . 
.... 2-5567 
3)9-1239 
Two volumes of mixed vapour . 
. . - . 3-0413 
Found 
Without at present offering any decided opinion as to the nature of this body, I may 
state that in repeated operations with large quantities of materials, I have entirely failed 
in obtaining pure zincmethyl by acting with zinc upon a mixture of ether and iodide of 
methyl. 
Repeated attempts to produce pure zincmethyl from zinc and iodide of methyl alone 
in the copper digester were also unsuccessful, although this method generally succeeds 
in small glass tubes. Iodide of methyl is not attacked by zinc at 100° C., even after long 
dipstion ; an admixture of 3 or 4 per cent, of ether is, however, quite sufficient to deter- 
mine the action at this temperature ; but with so small a proportion of ether the whole 
of the iodide is never decomposed, and it is impossible to effectually separate either this 
or the effier from the zincmethyl produced. When the digester containing zinc and 
pure iodide of methyl is heated to any temperature from 120° to 200° C., the iodide is 
decomposed ; but at the lower temperatures the decomposition is never complete, whilst 
at the higher ones little or no zincmethyl is produced, the methyl being resolved into 
gases. This anomaly m the results obtained from the same materials heated in a copper 
digester and in glass tubes, is doubtless due to the difference in the conditions obtaining 
m the two cases. In a glass tube half-immersed in a heated oil-bath, a distillation of 
the internal liquid is constantly going on, the vapour formed in the lower portion of 
the tube being condensed in the upper part exposed to the cooling influence of the air 
MDCCCLIX. q , ’ 
