Punctuation and spelling were made consistent when a predominant
preference was found in this book; otherwise they were not changed.
Simple typographical errors were corrected.
Ambiguous hyphens at the ends of lines were retained; occurrences of
inconsistent hyphenation have not been changed.
In the table of Ranges:
Transcriber rearranged parts of the column headings, but “as
follow” (singular) in the table’s title was printed that way in
the original.
The column heading “55 to 60°” was misprinted as “55 to 66°”;
corrected here.