Underscores “_” before and after a word or phrase indicate _italics_ in the original text. Equal signs “=” before and after a word or phrase indicate =bold= in the original text. Small capitals have been converted to SOLID capitals. Illustrations have been moved so they do not break up paragraphs. Typographical and punctuation errors have been silently corrected. Page 41: “1,000,000 feet or 300,000 kilometres per second” changed to “1,000,000,000 feet or 300,000 kilometres per second” _Translated from the Danish by $1 Fellow of the American-Scandinavian Foundation, 1923, and RACHEL T. LINDSAY_…
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