Faraday as a Discoverer. 197 
arrangements he places a metallic sphere in the middle of a 
large hollow sphere, leaving a space of something more than 
half an inch between them. The interior sphere was insulated, 
the external one uninsulated. To the former he communicated 
simi r in form, e interior sphere of each communicated 
with the external air by a brass stem ending ina knob. The 
took more than half the original charge. A portion of the 
charge was absorbed in the dielectric itself. The electricity 
took time to penetrate the dielectric. Immediately after the 
Power of permitting the charge to enter them in different 
degrees, Faraday figured their particles as polarized, and he 
concluded that the force of induction is propagated from par- 
ticle to particle of the dielectric from the inner sphere to the 
outer one. This power of propagation possessed by insulaters 
he calls their “Specific Inductive Capacity.” F 
Faraday visualizes with the utmost clearness the state of his 
Contiguous particles ; one after another they become charged, . 
each Succeeding particle depending for its charge upon its - 
Predecessor. And now he seeks to break down the wall of 
partition between conductors and insulators, ‘Can we not” 
he says, “by a gradual chain of association carry up disc 
from its occurrence in air through spermaceti and water to 
Solutions, and then on to chlorids, oxyds, and metals, without 
any essential change in its character?” Even copper, he urges, 
offers a resistance to the transmission of electricity. The action 
