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Isomerism caused much consternation to early researchers, since isomers have exact the same composition, but differ in configuration (arrangement) of the atoms. For example, there was much speculation for the chemical identity of benzene, until the correct structure was described by Friedrich August Kekulé. Likewise, the idea of stereoisomerism - that atoms have rigid three-dimensional structure and can thus form isomers that differ only in their three-dimensional arrangement - was another crucial step in understanding the concept of distinct chemical substances. For example, tartaric acid has three distinct isomers, a pair of diastereomers with one diastereomer forming two enantiomers | The Project Gutenberg EBook of Mathematical Geography by Willis E. Johnson This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org Title Mathematical Geography Author Willis E. Johnson Release Date February 21 2010 EBook 31344 Language English Character set encoding ISO-8859-1 START OF THIS PROJECT GUTENBERG EBOOK MATHEMATICAL GEOGRAPHY MATHEMATICAL GEOGRAPHY BY WILLIS E. JOHNSON Ph.B. VICE PRESIDENT AND PROFESSOR OF GEOGRAPHY AND SOCIAL SCIENCES NORTHERN NORMAL AND INDUSTRIAL SCHOOL ABERDEEN SOUTH DAKOTA NEW yORK CINCINNATI CHICAGO AMERICAN BOOK COMPANY Copyright 1907 By WILLIS E. JOHNSON Entered at Stationers Hall London JOHNSON MATH. .
