00634cam a2200193 4500 612005315 TxAuBib 20221208120000.0 221207s2022||||||||||||||||||||||||eng|u 69493 Project Gutenberg PGUSA eng TxAuBib Heffron, Ida Cassa. Lessons in chalk modeling [Gutenberg] : The new method of map drawing / Ida Cassa Heffron. Project Gutenberg, 2022. Project Gutenberg ; 69493 Public domain in the USA. Electronic text. Project Gutenberg ; 69493. http://www.gutenberg.org/ebooks/69493