THE ELECTRIC'AHD LUMINIFEROUS MEDIUM. 
211 
ai’e so excessively slow on account of its great inertia that viscosity might possibly 
in any case be neglected, yet it will not do to omit the studs and thus make the 
model like a model of a gas, for we require rotation of an individual sphere to be 
associated with rotation of the whole element of volume of the medium in which it 
occurs. Let then in the rotationally elastic medium a narrow tnbular channel be 
formed, say for simplicity a straight channel AB of uniform section : suppose the 
walls of this channel to be grasped, and rotated round the axis of the tube, the rota¬ 
tion at each point being proportional for the straight tube to AP“" + ; this 
rotation will be distributed through the medium, and as the result there will be lines 
of rotational displacement all starting from A and terminating at B : and so long as 
the walls of the channel are held in this position by extraneous force, A will be a 
positive electron m the medium, and B will be the complementary negative one. 
They will both disappear together when the walls of the channel are released. But 
now suj)pose that before this release the channel is filled up (except small vacuous 
nuclei at A and B which will assume the spherical form) with studded gyrostatic 
spheres so as to be continuous with the surrounding medium ; the effort of release in 
this surrounding medium will rotate these spheres slightly until they attain the state 
of equilibrium in which the rotational elasticity of the new part of the medium 
formed by their aggregate provides a balancing torque, and the conditions all round 
A or B will finally be symmetrical. We shall thus have created two permanent 
conjugate electrons A and B ; each of them can be moved about throuo’h the medium, 
but they will both persist until they are destroyed by an extraneous process the 
reverse of that oy which they are formed. Such constraints as may be necessary to 
prevent division of their vacuous nuclei are outside our present scope ; and mutual 
destruction of two complementary electrons by direct impact is an occurrence of 
infinitely small probability. The model of an electron thus formed will persist for 
any finite assignable time if the distribution of gyrostatic momentum in the medium 
is sufficientlj^ intense : but the constitution of our model of the medium itself of 
course prevents, in this respect also, absolute permanence. It is not by any means 
here suggested that this circumstance forms any basis for specnlation as to whether 
matter is permanent, or will gradually fade away, il'he position that we are con¬ 
cerned in supporting is that the cosmical theory which is used in the present 
memoirs as a descriptive basis for ultimate physical discussions is a consistent and 
thinkable scheme ; one of the most convincing ways of testing the possibility of the 
existence of any hypothetical type of mechanism being the scrutiny of a specification 
for the actual construction of a model of it. 
5. An idea of the nature and possibility of a self-locked intrinsic strain, such as 
that here described, may be facilitated by reference to the cognate example of a 
material ware welded into a ring after twist has been put into it. We can also have 
a closer parallel, as v.mll as a contrast ; if breach of continuity is produced across an 
element of interface in the midst of an incompressible medium endowed with 
2 E 2 
