NUCLEAR CONDENSATION OF CERTAIN ORGANIC VAPOURS. 
473 
negatively electrified. But when some of this alcohol was carefully purified—(I) by 
conversion into methyl oxalate and by subsequent hydrolysis, (2) by distillation after 
treatment with sodium—both products behaved alike and became negatively charged. 
The sign of the charge acquired by the liquids which have been examined when 
bubbled was as follows :— 
Electrification on Bubbling. 
O 
7 - -j Sign of charge 
lc f n< ' acquired by liquid. 
Liquid. 
Sign of charge 
acquired by liquid. 
Methyl alcohol .... 
Methyl butyrate .... 
Ethyl alcohol. 
Acetic acid. 
+ 
Iso-amyl alcohol .... 
Chloroform. 
— 
Ethyl acetate. 
Ethyl iodide. 
- 
Propyl acetate. 
Purification of Liquids. 
Methyl alcohol : (l) Kahlbaum’s alcohol was converted into methyl oxalate by 
anhydrous oxalic acid; the resulting oxalate was washed and hydrolised by sodium 
hydrate. The alcohol obtained was distilled, and then distilled from lime. (2) The 
same initial alcohol was treated with metallic sodium, and distilled. 
Ethyl alcohol : Distilled from lime from marble, and then from a small piece of 
sodium. Density at 12°, 0 - 7961 gms. per cubic centimetre. (Absolute alcohol has a 
density of (P7962.) 
Chloroform : Twice distilled, boiling point 61 ‘7° to 61'8° at 777 mm. 
Ethyl iodide : Once distilled. 
The other liquids were the same as were used in the Condensation experiments 
(see p. 452). 
The result for acetic acid is not in agreement with the double-layer theory, though 
the acid used had been purified by fractional crystallisation and distillation. It has 
been mentioned that other anomalous results have been obtained with this acid. 
Fog-like Condensation. 
Some observations were made to find the expansion necessary for fog-like condensation 
in certain organic vapours. But the point at which this kind of condensation took 
place was not usually sufficiently well defined for the results to be very exact; for, as 
the expansion was increased above that which caught the natural nuclei, the number 
of drops continuously increased. In this respect acetic, propionic, n-butyric, and 
iso-valeric acids, methyl butyrate, and propyl acetate are unlike water. Tertiary 
amyl alcohol behaves more like water : with it an expansion of 1 ‘27 gives many drops, 
the condensation becoming fog-like when the expansion is increased 1*28. 
VOL. CCVIII.- A. 3 P 
