— [26], l. 2, for “land,” read “level.”
— [27], l. 1, for “at the place,” read “at the right place.”
— [28], l. 29, for “reconnoitre,” read “reconnoissance.”
— [30], l. 3, for “A c d B,” read “A C D B.”
— [32], l. 2, the point m in the cut, is one whole division above C; it should be only three fourths of a division.
— [38], l. 10 from bottom, for “276,” read “268.”
— [39], l. 10 from bottom, for “142.13,” read “143.13”; and last line, for “58.46,” read “48.46.”
— [40], l. 7, for “10310,667,” read “10,277,333.”
— [42], l. 9, for “Thus,” read “These.”
— [42], l. 8 from bottom, for “2°.81 or 2° 48′.6” read “2°.86 or 2°.51.6.”