The Journal of the Royal Astronomical Society of Canada 1918-07: Vol 12 Iss 6 (1918)
Royal Astronomical Society of Canada · leaf 62
ould expand and contract exactly alike. In this way that source of error which is the most difficult to overcome in precise determinations of steel tapes would be elim- inated. For the above reasons, certain tapes have been selected as steel standards; they are carefully standardized at regular… … FRONT VIEW Fic. 18.—TArkE COMPARATOR—ZERO END
Astronomy · Scholarly Journals · Microfilm
Internet Archive · Public domain (published before 1931). Free to use for anything.
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