Thanks for the most interesting discussion of slinkys, "ether", and
seismology. But I'm a little vague on what you mean by "vibrations".
You're describing a field whose orientation isn't necessarily at a right
angle (transverse) to the direction of propagation (as in a TE or TM
mode wave), yet whose "vibrations" are nevertheless at a right angle to
the direction of propagation. So the "vibrations" are in a different
direction than the field. I'd like to learn more about this phenomenon,
but I can't find "vibrations" in the indexes of any of my
electromagnetics texts. Do they have another name?

Roy Lewallen, W7EL

Yes, "vibes." I think Peter is regressing back to the '60's.
73,
Tom Donaly, KA6RUH