177 
Percengate 
No. 1. 
No. 2. 
Calculated from the 
formula C 2 H 6 0 
c 
51*56 
..51-65.... 
52T7 
H 
12-99 
..1302.... 
1304 
O 
35*45 
..35*33.. . 
34-79 
10000 
10000 
10000 
The numbers are not all that could be desired when com- 
pared with the calculated, this is owing to the difficulty in 
burning so volatile a liquid, and to the small quantities 
taken. Dumas and Boullay {Ann. de Chimic, 1827, 36, 299) 
state that in order to obtain agreeing results upwards of a 
grm. of liquid was necessary, in one combustion 1’742 grms. 
were used, with ether a still greater quantity was required. 
The alcohol still remaining in the carbonate of potash and 
in the dilute solution was separated by distillation, this dis- 
tillate was oxidised by a mixture of bichromate of potash 
and sulphuric acid, when the characteristic odour of alde- 
hyde was recognised, the oxidation was continued until it 
had disappeared, on distilling to dryness an acid distillate 
was obtained, this was neutralised with pure carbonate of 
soda, and yielded on evaporation needle-shaped crystals of 
acetate of soda; the mother liquor was distilled to dryness 
with sulphuric acid, the distillate neutralised with pure 
carbonate of silver, filtered and boiled, on cooling it yielded 
colourless transparent flat needles, which, after drying over 
sulphuric acid, gave on analysis the following numbers. 
No. 1. 0-4142 grm. of salt gave 0.2663 grm. of metallic 
silver. 
No. 2. 0*5095 grm. of salt gave 0*3274 grm. of metallic 
silver. 
No. 3. 0-3650 grm. of salt gave, after drying at 100° C. 
in a water bath for one hour, 0-2349 grm. of metallic 
silver. 
No. 4. 0-2483 grm. of salt gave, after drying at 100° C. 
in a water bath for two days, 0-1604 grm. of metallic 
silver. 
