[INDEX]. The original index was structured in a way not suitable for this ebook. The white space on the printed page substituted for words not repeated. Thus, under "Balancing of aerodrome, … ", were indented entries for "engine", "wings and rudder", &c. This spacing has been rendered herein as a horizontal bar "—", one for each word to be understood as repeated. So in this case, two bars, meaning "Balancing of". Moreover, page numbers referenced by index entries were right-justified and preceded by dotted leaders. Herein, the leaders have been suggested by horizontal ellipsis "…".
Estimating from Internet Archive's stated scanning rate of 400 ppi, the pages were about 6.2 by 9.2 inches. Body text was printed in 9 point type, with 3 point leading, and footnotes were printed in 5.4 point type.