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; occasional unbalanced
quotation marks retained.
Ambiguous hyphens at the ends of lines were retained; occurrences of
inconsistent hyphenation have not been changed.
Redundant chapter titles have been removed.
The name “Van ’t Hoff” always was misprinted as “Van’t Hoff” in the
original book. That misprint has been retained here.
Page 40 of the Chemistry chapter uses Dalton’s symbols for the four
atoms in five molecules: a circle with horizontal lines (hl), a circle
with vertical lines (vl), a circle with a dot in its center (cd), and a
hollow circle (hc). If your text viewer cannot display those symbols,
the five molecules, in sequence, are: hl-cd, cd-vl-cd, vl-hc, hc-vl-hc,
and cd-hc.
Other pages in the Chemistry chapter contain diagrams of molecular
structures. Those diagrams only display properly when a fixed-width
font is used.
Subscripts in the Chemistry chapter are shown full-height, e.g., H2O.
Text sometimes expresses fractions with a dash instead of a slash. That
notation has been retained here.
Page 46: The original book used “Zu” as the symbol for zinc.
Page 122: “entirely changed by” was printed as “charged”; changed here.
Page 139: “barometric” was printed as “barometic”; changed here.