It is generating strength now.
3 seconds sound clip from Superman (1948) - Superman At Bay (Chapter 14).
You can hear this line at 00:14:15.504 in the Blu-ray version of the episode.
Quote context
[...]
- Oh, yes. It can be destructive even at this level.
- I want it turned on a certain spot at the city jail.
- I can beam at any designated spot and calibrate it so that it will work.
- Then hurry, there are two useless people to be wiped out.
- Are you sure that you want to loose such devastating power?
- It is generating strength now.
- Is Jimmy at his desk? Well, how about Clark? Let me speak to him.
- Clark, I'm in jail. No, not really. Just visiting.
- Have you had any word from Jimmy?
- What's the address? Go ahead. 1600 North Boulevard. I'll check him.
[...]