DE. E. EEANKLAira’S EESEAECHES ON OEGANO-METALLIC BODIES. 
68 
VIII. '3964 grm., similarly treated, gave 88’ 8 cubic centimetres dry nitrogen at 
10°’0 C. and 412*4 mm. pressure, equal to 46*19 cubic centimetres at 0°C. and 760 mm. 
pressure, or *05834 gramme. 
IX. *3712 grm. gave 84*0 cubic centimetres dry nitrogen at 411*8 mm. pressure and 
15° C., or 43*02 cubic centimetres at 760 mm. pressure and 0°C., or *05410 gramme. 
These numbers correspond with the formula 
C,H,ZnNO„ 
as is seen from the following comparison : — 
Calculated. 
vV 
Found. 
A 
C. . 
( — 
24 
26*22 
t 
I. 
25*69 
II. 
26*05 
III. 
25*09 
IV. 
V. 
VI. 
VII. 
VIII. IX.' 
H, . 
5 
5*46 
5*29 
5*29 
5*38 
N . 
14 
15*30 
15*32 
14*72 14*63 
Zn . 
32*52 
35*53 
35*63 
35*28 
35*16 
0 , . 
16 
17*49 
91*52 
100*00 
The substance used for these analyses was prepared in several different operations. 
That used for Nos. III. and IV. had undergone considerable oxidation, as it was finely 
powdered before being weighed, which will account for the deficiency in the per-centage 
of carbon. These results prove that the new body is formed by the union of an equal 
number of atoms of zincethyl and binoxide of nitrogen ; but from considerations given 
below, the above formula requires to be doubled, and I shall presently show that the body 
is a compound of zincethyl with the zinc-salt of a new acid, for which I propose the name 
Binitroethylic add. Its formula is therefore 
O, Zn+ZnC.H^. 
owing to the formation of some carbonate of zinc, which requires a higher heat for complete decomposition. 
Simpson’s absolute method gave very good results without the use of peroxide of mercury, hut it was found 
impossible to prevent the occurrence of a considerable amount of binoxide of nitrogen in the resulting gas. 
Even when it was made to stream over 12 inches of an intensely ignited mixture of copper turnings and 
copper reduced from the oxide, the resulting nitrogen stOl contained 10‘9 per cent, of binoxide. It was 
therefore necessary to estimate the volume of the latter gas by means of solution of protosulphate of iron, 
and to deduct half its volume from the observed amount of the mixed gases. The presence of protoxide of 
nitrogen would not interfere with the accuracy of the result, as this gas is unaffected by solution of proto- 
sulphate of iron, and contains exactly its own volume of nitrogen. By the observance of this precaution, 
Simpson’s absolute method not only appears to be capable of great accuracy, but it also requires much less 
expenditure of time, whilst it is easier of execution than any of the other methods, if it be employed in 
conjunction with the gas analysis apparatus, which I always use in eudiometrical operations (see J ournal of 
the Chemical Society, vol. vi. p. 200) ; the absorption-tube, containing a layer of concentrated caustic potash 
solution, being used to receive the products of combustion, at the conclusion of which, the determination of 
the absolute volumes of nitrogen and binoxide of nitrogen is effected with this apparatus in a few minutes. 
K 2 
