Part 13

Minor punctuation errors have been repaired. Hyphenation and accent usage have been made consistent.

The following amendments have been made:

Page 21--Labavius amended to Libavius--"... Libavius declares that he would sooner believe ..."

Page 88--repeated 'a' deleted--"... possibly a little imaginative, for she wrote not unsuccessfully; ..."

Page 118--it at amended to at it--"... and aim at it from precisely the same distance."

Page 175--Wolffii amended to Wolfii--"This fragment is preserved in "Wolfii Lectionum Memorabilium centenarii, XVI.:" ..."

Page 215--omitted word 'on' added--"Helgi and his brother Thorstein went on a cruise ..."

Page 222--multiplication sign changed to plus--"... but the sum of the digits 1 + 8 = 9."

The frontispiece illustration has been moved to follow the front matter. Other illustrations have been moved where necessary so that they are not in the middle of a paragraph.

Advertising material has been moved from the beginning of the book to the end.