POSITIVE ELECTRICITY RED RAY OXYGEN. 113 



brevity sake " radiant proper") on the surfaces of the com- 

 pound molecules, every degree of inflammability may be 

 attained, and that in PHOSPHORUS the entire of the poles radiant 

 proper are completely exhibited on the surfaces of its atoms, and 

 its transition is consequently voluntary and difficult to restrain. 

 While experimenting on Backhoffner's electro-magnetic 

 machine at Mr. Palmer's, of Newgate-street, of whom I pur- 

 chased it (and where many very interesting specimens of 

 philosophical apparatus are to be found), he was so good to 

 point out a curious phenomenon in electricity he had accident- 

 ally observed, and could not account for. On applying an 

 instrument of flat plate- glass, with the word Fire written in 

 extended parallel lines, with the usual dots of foil, and a dis- 

 charging ball of brass attached, he observed, on holding the 

 end of his thumb at about an inch distant from the foil on 

 the* WOODEN HANDLE, that a most brilliant and beautiful spark 

 of an inch in length, of distinct homogeneous RED light, was 

 obtained, and continued to be discharged, from a common elec- 

 trical machine, with a cylinder of about 12 to 14 inches in 

 length. 



The machine was charged with POSITIVE electricity, and 

 the colour of the light was of the intensity and brilliancy of 

 the RED prismatic ray of the solar beam. 



I repeated the experiment immediately in broad daylight, 

 and had the satisfaction to obtain an additional proof in corro- 

 boration of my views to the one kindly afforded me, by Mr. 

 Abraham of Sheffield, at the meeting of the British Associa- 

 tion at Liverpool, in September last, to which I have before 

 alluded, that oxygen and the red ray of solar light and POSI- 

 TIVE electricity are IDENTICAL. 



It is in substance mentioned in that excellent work, Dr. 

 Lardner's Cabinet Cyclopedia, in the volume containing that 

 admirable discourse on Natural Philosophy, by J. F. W. 

 Herschel, Esq., M. A., &c., late Fellow of St. John's, 

 Cambridge. 



