Quote: distances are equal if marks upon a practically-rigid body coincide permanently with corresponding marks on the other body

Quotation Skeleton

All practical geometry is based upon a principle … We will call that which is enclosed between … a tract marked out on it. These two … can be brought to coincide permanently with the … [p. 237 in the original] We now assume that: If two tracts are found to … of Euclid, but also its nearest generalization, the …   Google-1   Google-2

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Additional Titles

Quote: if two tracts are measured as equal once and anywhere, they are equal always and everywhere; a foundation for the general theory of relativity

Related Topics

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