This chapter is devoted to a translation of parts of the school-geometry text Geometrja dla trzeciej klasy gimnazjalnej by Zygmunt Chwiałkowski, Wacław Schayer, and Alfred Tarski. The text was published in 1935 by Państwowe Wydawnictwo Książek Szkolnych, the National Schoolbooks Publisher. Its title page is shown on page 276 of the present book. The note there under the publisher's logo says that the price of the book, including the cost of the stamp of the Society Supporting Construction of Common Public Schools, is 1.20 zlotys. That was comparable to the retail price of three kilograms of wheat flour, one kilogram of pork, five liters of milk, or thirteen eggs.