ECN Forum Forums General Topics of the Trade General Discussion Area BX ground clamp

The old house renovation I am looking over is a museum of wiring types. Knob and tube, BX, ungrounded cloth Romex (or whatever it's called), etc.

Here is a ground clamp (I did not follow it to the other end yet) on the armored cable...did this take a ground from or add a ground to the cable do you think?

I was hurrying thru a walk thru and did not get to investigate as much as I wanted.

OOPS! Here is the pic