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temperature. The author .showed that Dr Chiistisoii's discovery of 

 paraffine, of which Dr Reichenbach was necessarily ignorant, is in- 

 consistent with this view ; and detailed some experiments, by v/hich 

 he has rendered highly probable the existence in petroleum of 

 eupion, another of the products of destructive distillation. This 

 substance is a liquid of sp. gr. 0-655, boiling at 110", and very fra- 

 grant. The author obtained from the Rangoon petroleum a liquid of 

 sp. gr. 0-744, boiling at 180", and rather fragrant. The oil of tur- 

 pentine, as is well known, boils at 280", and has a sp. gr. of 0-860; so 

 that, at all events, the naphtha from the Rangoon petroleum is not 

 oil of turpentine. This was farther proved by the tests of nitric 

 acid and iodine. Similar experiments on one or two other species of 

 naphtha led to similar results. They all yielded a liquid of sp. gr. 

 about 760, and, consequently, could not be oil of turpentine. The 

 kinds of naphtha tiied were Persian naphtha, obtair.ed from Dr 

 Thomson, and commercial naphtha, sold by M. Robiquet of Paris. 



The author concluded, that if the naphtha examined by Reichen- 

 bach were genuine, there must be at least two kinds of naphtha; one 

 a product of destructive distillation, the other the oil of turpentine 

 of the pine forest of which our coal-beds are formed, separated by a 

 gentle heat, either before or after their conversion into coal. It is 

 obvious that our common coal-beds have never yet been exposed to a 

 heat sufficient for destructive distillation, since they are debtroyed by 

 a moderate heat, and we may therefore expect the petroleum of 

 these coal-beds to be of the kind described by Reichenbach ; while the 

 Rangoon and Persian petroleums, being products of destructive dis- 

 tillation, must have their origin, if in coal-beds at all, in such as have 

 been exposed to a high temperature, and must, consequently, be very 

 different from the ordinary coal-beds. In confirmation of this view 

 it may be stated, that Dr Christison could find no paraffine either in 

 the petroleum of St Catharine's, or in that of Trinidad or Rochdale. 



The author finally directed attention to the application of the pa- 

 raffine as a material for giving light, as, when pure, it burns uith a 

 clear bright flame, like that of wax, and might doubtless be obtained 

 at a cheap rate in the East. 



