to have the Properties of Polonium or Radium. 91, 
infinite distance : which is 
| 
® 
lL % 
ss) 
> 
U4 q a 
(Aep., Table * of § 20). 
§9. In fig. 1 the total quantity of the two electricities is 
Se of vitreous and e of resinous. Hence to. make a neutral 
or unelectrified combination of atoms and electrions we must 
add a combination electrically equivalent to 7 electrions. 
If we simply placed seven electrions in the neighbourhood of 
the combination shown in fig. 1, they would instantly ex- 
plode into the atoms: and the thus augmented combination 
might ultimately settle in two tetraelectrionic atoms moving 
from one another with some finite velocity, and each having 
its quartet in one of the stable configurations of ' equilibrium 
of four electrions within it, (Aep. §17). Or it might settle 
into any of a great number of possible configurations of 
two overlapping tetraelectrionic atoms with 8 electrions in 
some configuration of stable equilibrium within them. In 
any of these results the explosive energy for which we are 
planning is lost. We must therefore find another plan for 
supplying the 7e of resinous electricity. Any such plan 
involves essentially the addition of 8 or more electrions. We 
might try one atom containing vitreous electricity equal in 
amount to one electrion, and try to charge it with 8 elec- 
trions: which we should almost certainly find impossible. 
The simplest plan really is to take fourteen atoms each pos- 
sessing vitreous electricity equal to $e, and place within it 
one electrion. This would add to our vitreously electrified 
explosive combination represented in fig. 1, 14e of resinous 
electricity and 7e of vitreous ; and would so add an electrical 
equivalent of the required 7e of resinous electricity to make 
up a non-electrified explosive combination. 
§ 10. These fourteen atoms may be first put together in two 
groups of seven as shown in fig. 3 (p. 532), and then applied 
symmetrically on the right-hand and the left-hand sides of 
fig. 1, in planes perpendicular to the axis. By making these 
atoms very large in comparison with the two atoms of fig. 1, 
we avoid any great interference with the forces described in 
§§ 6, 7, 8; and by placing them so as to overlap one another 
slightly and to make the central atoms of the two groups of 
seven overlap slightly the atoms of fig. 1, we can, according 
to the last four lines of Aep. § 4, give any mutual forces we 
* In this table the quantity of vitreous electricity belonging to the 
atom is ¢ instead of je as at present. Thus instead of ¢? we have ie. 
202 
