<VV> Horn contact?

[Geoffrey Johnson]

The bellville spring comresses (flattens) and touches the center, 
exposed metal part of the wheel that the spring fits against.

>
> I'm puzzled about the horn this time.  Just where is contact made to the ground within the steering wheel when the horn ring is pressed?  The spring post contacts the contact ring and the bellville spring washer OK, but what is the path from the bellville washer to ground?  I can't see a path to anything and I'm wondering if I'm missing a part there that isn't clear in the manual.  Any ideas on this?