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through the aether. The forces acting on its material points eliminate each other. It follows, that this cannot be the case in , however, in system C all force-components perpendicular to the -axis are changed if one goes over from to , but the equilibrium will not be disturbed as they are changed in the same ratio. In this way it can be seen, that when is the state of equilibrium of the body during the displacement in the aether, is the state of equilibrium when the displacement doesn't exist. One therefore comes exactly to the influence of motion on the dimensions, which was shown before to be necessary to explain Michelson's experiment.
Of course we cannot ascribe great importance to this result; the transfer to molecular forces of what we have found for electrical forces, may be too risky for some. Moreover, if we want to do this, it remains undecided whether earth's motion shortens the dimensions in one direction - as it was supposed before - or elongates the length perpendicular to it, by which assumption we could reach the same result.
Anyway, it seems undeniable that changes of the molecular forces and consequently of the body's size of order are possible. Michelson's experiment thus loses its verification power for the question at which it was aimed. If one assumes the theory of Fresnel, then its meaning rather lies in the fact, that we can learn something about the change of dimensions.
As , then is the two hundred millionth. A contraction of the diameter of the Earth by this ratio would amount 6 cm. We cannot speak about the observation of a change in length of two hundred millionth when comparing meter sticks, and even if an observation method would allow this, then this method would be the juxtaposition of two sticks, but we would never detect the discussed changes, when they occur in the same way for both of them. The only remedy is to compare the length of two sticks perpendicular to each other,
