240 Intelligence and Miscellaneous Articles. 



tims. length and 2 centiins. diameter, to the ends of which additions 

 were attached (by fusion) containing the conducting-wires, so that 

 in the experiment the wires were at least 45 centims. distant from 

 each other. The tube was filled with phosphorus vapour of very 

 little tension ; after the experiment its sides were coated with a 

 thin layer of amorphous phosphorus brownish red changing to 

 golden yellow, and in many places exhibiting the colours of thin 

 films. 



The second apparatus serving for the same purpose, a master- 

 piece of the glassblower's art, has the form and size of a beaker- 

 shaped double-walled champagne-glass. The thin layer of amor- 

 phous phosphorus distributed over the inner surfaces of its walls 

 exhibits the play of all the colours of thin films, giving to the glass 

 a pleasing appearance. 



The third, still more elaborately executed apparatus is designed 

 to show that the conversion of the phosphorus is effected even by 

 the inducing action of the current. For this purpose the ends of 

 the two aluminium conducting-wires are inserted in exhausted 

 spheres in which there is no phosphorus. These spheres are en- 

 closed in others, which are united by a tube 40 millims. long and 1 

 millim. wide. The interspaces thus formed, likewise exhausted, 

 contain the phosphorus, which is therefore completely shut off from 

 the conducting-wires by a wall of glass. The distance between the 

 conducting-wires amounts to 26, and the diameter of the outer 

 spheres to 5 centims. The interval between the walls of the 

 spheres amounts to 5 millims. Here also the inner side of the 

 outer, and the outer side of the inner sphere, in like manner as 

 above stated, were coated with amorphous phosphorus. Only in 

 the narrow connexions was no phosphorus deposited. 



The above-mentioned facts furnish, perhaps, the best demonstra- 

 tion that the conversion of phosphorus into the amorphous modifi- 

 cation is effected neither by the light nor by the heat which accom- 

 pany the current, but exclusively by the electricity itself. 



The instructive experiments which Hittorf published in 1865 

 (Pogg. Ann. vol. cxxvi. p. 195) were made with another arrange- 

 ment of the apparatus, as the platinum wires, fused into glass 

 spheres of 6 to 8 centims. diameter, were only a few millims. dis- 

 tant from one another ; so that sparks passed, and the course of 

 the phenomenon was somewhat different from that above described ; 

 but the conclusions deduced therefrom by Hittorf were the same. 



I hope to be able to resume this subject in greater detail ; for 

 the present the above account may suffice to recall attention to it. 

 — Poggendorff's Annalen, vol. clii. pp. 171-173. 



