the Petroleum of Rangoon. 127 



tity has alone prevented me from pushing the purification 

 further. 



From these experiments, I consider myself entitled to con- 

 clude, that the petroleum of Rangoon contains eupione in very 

 considerable quantity ; and, as Dr Christison has already shewn 

 that paraffine may be extracted from it, we can no longer doubt 

 that it has been produced at a high temperature, or, in other 

 words, that it is a product of destructive distillation. 



Dr Christison, in his original paper on petroline, mentioned 

 that a quantity of oil, sent by Mr Swinton to the Society as 

 pure Persian naphtha, appeared to be pure oil of turpentine, 

 which he concluded to have been substituted for the naphtha. I 

 at first thought from Dr Reichenbach's experiments, that it 

 might have been at once genuine naphtha, and genuine oil of tur- 

 pentine ; only, in this case, it must have been of that species of 

 naphtha, which, like the artificial naphtha distilled from coal at 

 212° by Reichenbach, is not the product of destructive distilla- 

 tion. But Mr Swinton states that it has not the characters of 

 true Persian naphtha, and although he was persuaded at the 

 time that he had sent genuine naphtha, he is now convinced that 

 a mistake has been committed. The Persian naphtha described 

 and analyzed by Dr Thomson some years ago, of which he was 

 kind enough to send me a small specimen, has again the charac- 

 teristic odour of the Rangoon naphtha, indicating the presence 

 of eupione. Dr Thomson obtained, by rectification, naphtha of 

 .753, and boiling at 320° ; while the eupione first described by 

 Reichenbach boiled almost precisely at the same temperature, 

 and had the sp. gr. .740. Some naphtha sold in Paris for pre- 

 serving potassium, which is colourless and very free from oxygen, 

 yielded to me by two successive rectifications, a liquid of sp. gr. 

 755, almost exactly that of Dr Thomson's rectified Persian 

 naphtha. Saussuke obtained from the naphtha of Amiano, a li- 

 quid of sp. gr. 758, boiling at 186°, thus approaching more near- 

 ly to the boiling point of Eupione. 



