The sideways "T" is a "F" for FLUSSTAHL KRUPP ESSEN. The only "R.W." I can think of offhand is Aug. Richard Weisheit. I've seen the mark, sig rune/single rune( http://en.wikipedia.org/wiki/Sig_Rune ) on a Simson from the mid 1930s with Boehler tube I think. I don't know which tube maker was into the occult. Is the mark like the Sig Rune?

Kidn Regards,

Raimey
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