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opposite variations of the dimensions.

If we assume, that the arm lying in the direction of Earth's motion, is shorter by

$L\cdot {\frac {{\mathfrak {p}}^{2}}{2V^{2}}}$

than the other one, and simultaneously the translation would have an influence which follows from Fresnel's theory, then the result of Michelson's experiment is fully explained.

Consequently we have to imagine, that the motion of a rigid body, e.g. a brass rod or of the stone plate used in later experiments, would have an influence on the dimensions throughout the aether, which, depending on the orientation of the body with respect to the direction of motion, is different. E.g, if the dimensions parallel to the direction of motion would be changed in the ratio of 1 to $1+\delta$, and the dimensions perpendicular to them by a ratio of 1 to $1+\epsilon$, than it should be

$\epsilon -\delta ={\frac {{\mathfrak {p}}^{2}}{2V^{2}}}$

(119)

Here, the value of one of the magnitudes $\delta$ and $\epsilon$ would remain undetermined. It could be $\epsilon =0,\ \delta =-{\frac {{\mathfrak {p}}^{2}}{2V^{2}}}$, but also $\epsilon ={\frac {{\mathfrak {p}}^{2}}{2V^{2}}},\ \delta =0$, or $\epsilon ={\frac {{\mathfrak {p}}^{2}}{4V^{2}}}$, and $\delta =-{\frac {{\mathfrak {p}}^{2}}{4V^{2}}}$.

§ 91. As strange as this hypothesis would appear at first sight, nevertheless one must admit that it's not so far off, as soon as we assume that also the molecular forces, similarly as we now definitely can say it of the electrical and magnetic forces, are transmitted through the aether. If this is so, then the translation will change the action between two molecules or atoms most likely in a similar way, as the attraction or repulsion between charged particles. Now, since the shape and the dimensions of a fixed body are, in the last instance, determined by the intensity of the molecular effects,