Read This!

The MAA Online book review column


Briefly Noted

Short Reviews by Fernando Q. Gouvêa

November 1999

There are lots of textbooks on elementary number theory, so when a new one comes out one has to ask what it has to offer that's new. In the case of James Tattersall's Elementary Number Theory in Nine Chapters, the first thing that is immediately apparent is the author's interest in and deep knowledge of the history of the subject. Beginning with the title, which alludes to the title of a famous Chinese mathematical text, the book is full of historical information, historical motivation, and (best of all) problems derived from these historical sources. The table of contents includes the standard list of topics for a first course in number theory, ranging from primes and divisibility through congruences, quadratic reciprocity, continued fractions, and the usual applications to cryptology. The book goes on to treat a more unusual topic, the theory of partitions, including a discussion of generating functions. In contrast to far too many mathematics books, the book has lots of text surrounding all the mathematical formulas. It's all a very rich mix, and I suspect students would enjoy using this book; I also suspect they would find it quite challenging.

Tattersall's Nine Chapters came out just a week or so too late for me to select it for my Number Theory course this spring. Next time around, it'll be high on the list of possible textbooks for the course.

Mathematics at Work is a book that challenges our assumptions about our subject. This is the fourth edition of a book devoted to

Practical Applications of Arithmetic, Algebra, Geometry, Trigonometry, and Logarithms to the Step-by-Step Solutions of Mechanical Problems, with Formulas Commonly Used in Engineering Practice and a Concise Review of Basic Mathematical Principles.
Browsing through the book reveals an amazing mix of topics, from very elementary stuff about divisibility to rather sophisticated chapters on plane and spatial geometry. Many pages contain elaborate tables of results on trigonometric functions, solving triangles, factoring expressions, and so on. Many specific construction problems are considered too, such as (to choose an example at random) how to find the "radius of a circle tangent to a given circle and to two lines at a given angle." There is a whole section on approximate formulas which includes a rather sophisticated discussion of where such formulas come from and how one might decide whether it is OK to use them. There is a chapter on "gear ratio problems", which turns out to be about continued fractions. At the back, there are dozens of tables giving all sorts of interesting and useful functions (one wonders why, in an age of calculators, one would need tables of common logarithms or trigonometric functions, but there they are).

I find this a fascinating artifact. On the one hand, it can be an excellent source of "real world" problems for those of us who teach elementary mathematics. Many of these problems are quite interesting, and some are quite difficult; in fact, I'd probably have trouble solving some of them on my own. On the other hand, it reflects a perspective on what mathematics is all about that I find deeply alien. This mathematics is about vast collections of apparently unrelated facts that one looks up as needed. (So, for example, there are not only tables indicating how the sines and cosines of complementary and supplementary angles are related, but also similar tables for tangents, cotangents, secants and cosecants!) Here is mathematics as a tool, but perhaps also as less than a science.

It is cause for joy and celebration that the "Sources" subseries of the AMS/LMS "History of Mathematics" series continues to grow. This book, which is volume 17 in the AMS/LMS history series, contains a small book by Jacques Hadamard on the connections between non-Euclidean geometry and the theory of automorphic functions. Hadamard's book was written in the 1920s for publication in Russia, appearing in a series entitled "The Geometry of Lobachevskii and the Development of Its Ideas". It was translated into Russian, and the original French text seems to have been lost; what we have here, accordingly, is a translation from the Russian edition. It is preceded in this edition by a "Brief History of Automorphic Function Theory, 1880-1930" by Jeremy Gray. This is short but helpful, emphasizing the very distinct approaches to the subject used by Poincaré and by Klein, leading to differing French and German approaches to the subject. Hadamard's essay belongs firmly in the French camp, with a strong emphasis on solving differential equations and also with characteristic foundational weaknesses. This little book should be of interest both to historians seeking to understand the evolution of the theory of automorphic functions and to mathematicians working in the area, and thus it is a valuable addition to the (rather short) list of original source material available in English translation. Keep them coming, AMS!


Publication Data

James J. Tattersall, Elementary Number Theory in Nine Chapters. Cambridge University Press, 1999. Softcover, 407pp, $24.95. ISBN 0-521-58531-7.

Holbrook L. Horton, Mathematics at Work, edited by Henry H. Ryffel, Edward E. Messal, and Robert E. Green. Industrial Press, 1999. Softcover, 687pp. $22.95. ISBN 0-8311-3083-0.

Jacques Hadamard, Non-Euclidean Geometry in the Theory of Automorphic Functions, edited by Jeremy J. Gray and Abe Shenitzer (American Mathematical Society and London Mathematics Society series in the History of Mathematics, volume 17). American Mathematical Society, 1999. Softcover, 95pp, $19.00. ISBN 0-8218-2030-3.


Back Issues:


Go to...

Find out...


Read This! is the MAA Online book review column. Contributions are welcome; contact the editor if you'd like to be one of our reviewers. Books for review should be sent to the editor: Fernando Gouvêa, Dept. of Math&CS, Colby College, Waterville, ME 04901. Publishers, please check our reviews information page.


Copyright ©1999 The Mathematical Association of America

MAA Online is edited by Fernando Q. Gouvêa (fqgouvea@colby.edu).
Last modified: Thu Nov 18 12:51:27 -0500 1999