Morton Salt

Hello Coilbuilders,
This is a cry for Help ! Can Anybody give me the formula of Mortons Salt ?
I am new to this group and still constructing my Tesla-Coil. I decided to build
everything myself because it is cheaper.
I also decided to build the capacitors myself. I chose a saltwater-design. The
salt which is used is supposed to be "Mortons-Salt". 
I have no idea at all what Mortons Salt is. As I live in Germany I must know
the German name for it, but I could find no explanation at all in any of my
If somone can give me the formula, or the name according to the UIPAC
standards, I will know what it is, and I will be able to detemine the German
name for it. Thanks in advance,
Regards, Erik.