528 Extracts from the Zoological Journal. [Sept. 



the conclusion that naphtha in general is not a product of destructive distillation, 

 and consequently, must have been separated at a comparatively low temperature. 



The author showed, that Dr. Christison's discovery of paraffiue, of which Dr. 

 Reichenb ach was necessarily ignorant, is inconsistent with this view ; and detailed 

 some experiments, by which 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°, aud very fragrant. The 

 author obtained from the Rangoon petroleum a liquid of sp. gr. 0*744, boiling 

 at 180 g , and rather fragrant. 



The oil of turpentine, as is well known, boils at 280°, and has a sp. gr. of 0*860 i 

 bo 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 tried were Persian naphtha, 

 obtained from Dr. Thompson, and commercial naphtha, sold by M. Robiquet, 

 at Paris. 



The author concluded, that if the naphtha examined by Reichenbach were 

 genuine, there must be two kinds of naphtha ; one a product of destructive 

 distillation, the other the oil of turpentine of the pine forests 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 destroyed 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 distillation, 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 oridinary coal-beds. In confirmation 

 of this view, it may be stated, that Dr. Christison could find no paraffine either 

 in the petroleum of St. Catherine's or ia that of Trinidad or Rochdale. 



The author finally directed attention of the application of the paraffine as a 

 material for giving light, as, when pure, it burns with a clear, bright flame, like 

 that of wax, and might doubtless be obtained at a cheap rate in the East. — Edin. 

 Phil. Journ. 1835. 



[Since the above was in type, we have received a copy of the papers, and a 

 specimen of the paraffine from Mr. G. Swinton, with a list of queries which we 

 will endeavour hereafter to resolve. — Ed.] 



3.— Extracts from Proceedings of Zoological Society of London.- — 1834. 



August 12. — A collection of land and fresh-water Shells, formed in the 

 Gangetic Provinces of India by W. H. Benson, Esq., of the Bengal Civil Service, 

 and presented by that gentleman to the Society, was exhibited. It comprised 

 forty species, and was accompanied by a descriptive list prepared by the donor, 

 and also by detailed notices of some of the more interesting among them. These 

 notices were read : they are intended by Mr. Benson for publication in the 

 forthcoming No. of the ' Zoological Journal.' 



From the time that he first became acquainted with the animal of a shell 

 resembling in all respects, except in its superior size, the European Helix lucida, 

 Drap., Mr. Benson regarded it as the type of a new genus of Helicidce interme- 

 diate between Stenopus, Guild., and Helicolimax, F6r. He had prepared a 



