Spike told us:
>JW, other earlier forms of distance communication were also EMF.
> smoke signals -- light (EMF) reflected from them is intercepted by our
> semiphore -- see above
> sign language -- see above
> Paul Revere's lanterns -- (one if by land, two if by sea, EMF)
>Other than war drums, I cannot think of *any* long distance communication
>does not rely on EMF. The ETIs will grok this, I can assure you. spike
What about carrier pigeon?:)
But truly, all processes that we detect are mitigated by EMF.