p. 501: but the tampers had had[del 2nd had] previous experience p. 508: shown on Plates VI to IX[VI, VII, VIII, IX[to accomodate links]] p. 516: at this place there is a considererable[considerable] area p. 538: based on the following rates and and[del 2nd and] percentages p. 579: by crossing the river, build-the[building the] reservoir p. 550: [For Table 14: added "Total materials cost"] p. 566: respectively (Fig. 5)[(Fig. 4)], together with lack of p. 584: [Table 17 renamed to Table 18 to avoid duplication.] p. 584: Table 17[18], compiled by the writer, shows how very extreme * * * * *