Punctuation, hyphenation, and spelling were made consistent when a predominant preference was found in this book; otherwise they were not changed.

Simple typographical errors and unbalanced quotation marks were corrected.

To make this eBook easier to read, particularly on handheld devices, some images have been made relatively larger than in the original pamphlet, and centered, rather than offset to one side or the other; and some were placed a little earlier or later than in the original. Sidebars in the original have been repositioned between chapters and identified as “[Sidebar (page nn):”, where the page reference is to the original location in the source book. In the Plain Text version, the matching closing right bracket follows the last line of the Sidebar’s text and is on a separate line to make it more noticeable. In the HTML versions, that bracket follows the colon, and each Sidebar is displayed within a box.

Sidebar “The Marines’ Zippo Tanks” (originally on page 37) used both “Mark I” and “Mark 1”. Here, all of them are “Mark I”.