Punctuation, hyphenation, and spelling were made consistent when a predominant preference was found in the original book; otherwise they were not changed.
Simple (and frequent) typographical errors were corrected; unbalanced quotation marks were remedied when the change was obvious, and otherwise left unbalanced.
Footnotes have been sequentially renumbered to make them unique, and then moved to the ends of the articles to which they belong.
Illustrations and references to them have been sequentially renumbered.
Pages 344, 345: Text shown as boldface was printed in a Blackletter font.
Footnote 30, originally on page 368: The page range was printed as shown (with dashed placeholders); the missing numbers may be 369 and 370.
Transcriber added a footnote link to the caption of Figure 2, as the footnote explains the abbreviations used in the illustration.
Footnote 46, originally on page 382: The citation for “Proc. Bos. Soc. Nat. Hist.” had no further details.
Page 411: Text uses both “Schiefergesteinen” and “Schiefergestenien”.
Footnote 60, originally Footnote 7 on page 411, omitted the page number reference.
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