Page 11, period changed to a comma (pushed up, with a slot)

Page 15, "porus" changed to "porous" (the porous plasters)

Page 15, "shelfs" changed to "shelves" (of store shelves)

Page 18, period added to abbreviation (No. 1 they)

Page 19, "willling" changed to "willing" (and willing to persevere)

Page 20, "corrigated" changed to "corrugated" (The corrugated band)