62 
DE. E. EEAJS^KLAJSD’S EESEAECHES ON OEGANO-METALLIC BODIES. 
In each operation about three ounces of zincethyl in ethereal solution was placed in 
the copper cylinder A, and the condensing syringe being attached, about twenty atmo- 
spheres of dry binoxide of nitrogen were introduced ; the syringe was unscrewed and 
the cyhnder A agitated for two or three minutes by rolling upon the floor or otherwise ; 
at the end of which operation, the pressure within A was found to be reduced to three 
or four atmospheres ; the process of condensation and agitation being repeated flve or 
six times, the copper cylinder becomes so much heated as to require immersion in cold 
water for a few minutes. At this stage of the process it is also desirable to allow the 
residual gas in A to escape. 
This gas consists principally of protoxide of nitrogen and hydride of ethyl ; the latter 
derived from the decomposition of zincethyl by a trace of aqueous vapour introduced with 
the binoxide of nitrogen. By repeating the above series of operations six or eight times, 
the zincethyl becomes saturated and the process is completed. If it be desned to obtain 
the crystalline compound in a state of perfect purity, it is better to place the zincethyl in 
a wide glass tube open at top and fitting into A ; but in this case very moderate agita- 
tion only can be used, and consequently the absorption takes place more slowly, and 
the operation requires two or three days for its completion. It is, however, rarely neces- 
sary to have recourse to this modification of the process. 
At the conclusion of an operation conducted as above, with the intervention of a glass 
tube, the contents of the latter consisted of a mass of colourless ciystals immersed in an 
ethereal solution 5 the latter was poured off and the former were freed from ether, by 
plunging the tube in a water-bath at 90° C. and passing through it a stream of diy 
carbonic acid. The resulting crystalline mass attracted oxygen from the air with such 
avidity, as to burst into flame when any considerable quantity was freely exposed; it 
was also instantly decomposed by water, and was therefore transferred at once into small 
glass tubes, which were then immediately sealed hermetically. 
Submitted to analysis these crystals yielded the following results : — 
I. -6476 grm., burnt with oxide of copper and free oxygen, the usual precautions 
being observed, yielded •6101 grm. carbonic acid and ’3084 grm. water. 
II. 'GllO grm. gave ’5836 grm. carbonic acid and '2909 grm. water. 
III. "4988 grm. gave ‘4588 grm. carbonic acid and '2413 grm. water. 
IV. *8892 grm., treated first with water and then with boihng nitric acid, yielded on 
subsequent ignition -3940 grm. oxide of zinc. 
V. -4179 grm., similarly treated, gave '1837 grm. oxide of zinc. 
VI. ’5900 grm. gave •2686 grm. oxide of zinc. 
1/11. *1166 grm., treated according to Simpson’s method, gave 62‘5 cubic centimetres 
of dry nitrogen at 9°-2 C. and 210-3 mm. pressure, equal to 14-04 cubic centimetres at 
0°C. and 760 mm. pressure, or •0177 gramme*. 
* Considerable difficulty was at first experienced in determining the nitrogen in this and the following 
compounds. The method of "Will and Vakbexteapp is quite inapphcahle, as it does not in some cases 
convert more than one-half of the total nitrogen into ammonia. Bunsen’s method also yields vaadahle results, 
