24 ON PETROLEUM AND PHOTOGEN. 



cause why its great merits have been in a measure lost sight of. I have 

 recently ascertained some new localities where it is attainable, and I 

 have urged one of my sons to undertake its culture. I have some plants 

 growiug in my garden borders, where any one can have the privilege 

 of examining them. In regard to the Red -flowered Sarracenia, a reme- 

 dial which arrests the small-pox in twelve hours, it is also a native of 

 our island, and is found in moist localities, on the borders of ponds, and 

 in white cedar swamps. It is now becoming very generally applied, 

 and, I understand, always with successful results. 



Flushing, Long Island, N. Y., May, 1863. 



ON PETROLEUM AND PHOTOGEN. 



BY W. PROCTER, M.D., F.C.S. 



The discovery, in 1825, by Dr. Faraday, of benzole in the products 

 of the distillation of oil, and the numerous applications which were 

 made of it, may be said to be the origin of those investigations into the 

 substances produced by the distillation of coal which have led to results 

 of the utmost importance, viewed either in a scientific, economic, or 

 commercial aspect. The two most valuable are the discovery of aniline 

 with its wonderful dyes, and the coal and other illuminating and lubri- 

 cating oils. It is to the latter of these two subjects that the present 

 paper is devoted.. 



The ancient inhabitants of different parts of the world, both civilised 

 and barbarian, were acquainted with natural oils which flow from the 

 earth, such as mineral oil, or petroleum, naphtha, bitumen, &c, and 

 used them for illuminating and other purposes. In Egypt, a substance 

 derived from petroleum was employed for embalming bodies, and in 

 some neighbouring countries asphalt is used to cover the roofs of houses 

 and coat boats. Mixed with grease, the Trinidad asphalt is applied to 

 the sides of vessels to prevent the borings of the teredo, and with lime 

 is used as a disinfectant. The Persians, Burmese, and other nations, 

 still continue to employ these substances, in their crude state, to give 

 light, and for medicinal purposes. 



In addition to these natural sources, similar compounds have long 

 been obtained by the distillation of coal and other allied minerals. As 

 early as 1694, Erie, Hancock, and Portlock "made pitch, oyl, and tar 

 out of a kind of stone, and obtained patents, therefore." In a work in 

 1791, by Lewis, on Materia Medica, it is stated that oils were distilled 

 from black bituminous shale. The early papers, also, of the Royal 

 Society, give accounts of the distillation of oils from coals and other 

 bituminous substances. In 1781, Lord Dundonald obtained a patent for 



