Emanations of Phosphorus through Air and other Media. 401 



proportional to the average charge (positive or negative) 

 carried by each, Akne is the total quantity of free electricity 

 of both kinds promiscuously carried to A per second. Thus 

 hne is the equivalent of conductivity. The rate of discharge 

 of A is thus —dQ/dt=(Y/x)Akne, where the constant of pro- 

 portionality is contained in e. The potential of the charged 

 plate of area A, the other being earthed, is therefore 

 Y = Y €~ Aknet / Cx in the lapse of time after charging to the 

 initial potential V , C being the capacity of the condenser. 



The conveyance of charge into the ionized region would be 

 similarly explained, virtually in the way of Clausius. Through 

 any interface in the ionized region, two such prisms may be 

 imagined travelling in opposite directions. They travel to 

 and from a boundary. The motion of the prism h is an 

 abstraction, but if I accentuate it here, I do so because in 

 the present investigation with phosphorus it may run closely 

 parallel to the actual state of things. When the phosphorus 

 grid is placed on a smooth clean surface, the position of the 

 disks is soon marked by apparent grease-spots due to deli- 

 quescing phosphoric oxide which has diffused across. Virtually 

 therefore an outgoing current originating in the phosphorus 

 is continually kept up, whether electricity is demonstrably 

 conveyed or not. 



To summarize : Instead of operating with the velocity 

 U(V/#), I have used the constant absorption-velocity k, found 

 in the absence of an electric field *. Thereafter I have 

 endeavoured to account for the inevitable factor V/a? or 

 dY/dcc, by associating it with the conditions of discharge of 

 the plate A. 



The only other explanation which I can suggest would be 

 an hypothesis whereby the ions in certain cases like the 

 present are released out of nuclei by the presence of a field. 

 In fact this is bluntly about the drift of the computations in 

 the above paragraphs, 8 and 9. 



12. The remainder of the paper will be devoted to a number 

 of promiscuous experiments. I shall endeavour to ascertain 

 whether the ionized particles exhaled by phosphor as are 

 accompanied by some form of obscure radiation, or whether 

 the reaction is restricted to an oxidation, the products of which 

 at first escape in gaseous form. This is best done by placing 

 barriers of thin material between the plates of the condenser, 

 care being taken to prevent the nuclei from passing around 

 the barrier, yet allowing sufficient space for access of air. It 

 was my plan to fold sheets box-like around the phosphorus 



* Beinembering that k is replaced by 3& if but -J of all the ions travel 

 in a given cardinal direction, roughly speaking. 



