The numbering of illustrations in the book is inconsistent. Illustrations that have no numbered captions may or may not be counted; this has not been standardised, except as listed below. Missing illustration numbers have been added only where they are referenced in the text. The illustrations referred to in the text as Figs. 242 and 243 are captioned Fig. 243 and 244.
Page 65-69 and Figs. 66-71: the text uses upper case reference letters, the illustrations lower case, which has not been standardised.
Page 84, table of symbols: the source document uses letters (O and L) rather than symbols for circle and angle.
Page 94, Bisect two of the angles A C of the triangle: presumably the unmarked point A is in the lower left-hand corner of the illustration.
Page 113, The tee-square, as shown, ...: there is no illustration with the relevant reference numbers; probably the reference is to Fig. 151/152.
Page 239, rough irregular lines, as in fig. 134, on page 131: there is no Fig. 134 on page 131; page 134 nor page 131 show the rough irregular lines. Several other illustrations in the book do show such lines.
Index: the order of entries is as printed in the source document.
Changes made:
Illustrations and Notes have been moved out of text paragraphs.
Some obvious minor punctuation and typographical errors have been corrected silently.