what does equality discover in chapter 3? how important is this discovery?

Equality 7-2521 announces that in his experiments he has discovered a new aspect of nature. Although he might be punished for his thoughts, he has begun to realize that the Council of Scholars does not know everything that is to be known. Only those who look for nature's secrets are able to find them.

Equality 7-2521 does not know the origins of the particular power he has discovered, but, when he experiments on a dead frog, he sees its leg jerking. After many experiments, he finds that the copper wire on which the frog hangs has somehow combined with the metal in his knife to create the leg jerk. He puts a piece of copper and a piece of zinc into a jar of salty water and connects them with a wire to create this new power. This power (electricity) would change the world from darkness to light both literally and figuratively. 

He discover the power of electricity and then pursues further exploration of the tunnel to see what else he can find.