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 directed aether wind (vent relatif de l’éther) of same absolute amount

of relative aether velocity.

The imagined rotation of the system shall happen counter-clockwise ($$L*$$)



thus the relative aether circulates clockwise ($$R*$$) in relation to the system imagined as being at rest.



Of the two light rays denoted by $$R$$ and $$L$$, which are circulating clockwise and counter-clockwise, one (namely ray $$R$$) at first travels faster away from $$O$$, then in the same measure faster around the whole circle, and also faster back to point $$O$$; the other one, $$L$$, is held back in the same way. –

When any wave is transmitted faster or held back by a relative stream $$v$$ of the wave-carrying medium, then it's known that (in first approximation), the time $$\Delta T $$ of earliness or delay is defined – with respect to normal time $$T$$ employed at standard velocity $$c$$ – by

$\frac{\Delta T}{T}=\frac{v}{c}$,

in case the directions of $$v$$ and $$c$$ coincide or are precisely opposite; instead of time $$\Delta T$$ one can also introduce the (apparent) path-contraction or -elongations $$\Delta U$$, then $$\Delta U$$ is defined – with respect to the normal path ("real" path) – by

$\frac{\Delta U}{U}=\frac{v}{c}$