Integrated Feeding Integrated

Are you doing this by removing the jumpers (pre out/main in) in each INT?

If so, the second INT will only be a power amp and "it's" volume control will be bypassed. I would set it at 0 though.

What are the two integrated amps, and what is the purpose of using both of them?

Assuming that there are no external jumpers on the integrated you will be using as an amp, you're basically plugging one active preamp into another. It can be done. I've tried it a couple of times and saw no benefit do doing it this way, except if you are trying to integrate a 2 channel system with a theatre. If integrated 1 has a better pre section than integrated 2, the lesser preamp in int 2 will still be in the signal path. The best you can hope for is some type of EQ effect that may hide something you don't like about the pre in int 2.