The Air Force Brain Booster Book
by John C. Sparks, 2006, 58 pages, 0.8MB, PDF

Amusements in Mathematics
by Henry Ernest Dudeney, 1917, 259 pages

Analysis of Puzzles
by Umesh Nair, 2006, 88 pp, 310KB, PDF

A Brief History of Mathematics
by Karl Fink, 1900, 366 pp, multiple formats

The Canterbury Puzzles and Other Curious Problems
by Henry Ernest Dudeney, 1919

A Century of Mathematics in America
by Peter Duren, Richard A. Askey, 1988, 3 volumes, 35 PDF files, 74MB

A Cultural Paradox: Fun in Mathematics
by Jeff Zilahy, 2010

A Defence of Free-Thinking in Mathematics
by George Berkeley

An Episodic History of Mathematics
by Steven G. Krantz, 2006, 483 pp, 1.6MB, PDF

Famous Problems in the History of Mathematics
Isaac Reed, 1998, The Math Forum

Flatland: A Romance of Many Dimensions
by Edwin A. Abbot, 2008, 96 pages, 610KB, PDF

Geometric Exercises in Paper Folding
by T. Sundara Row, 1917, 176 pp, multiple formats

Greek Geometry from Thales to Euclid
by George Johnston Allman, 1877, 248 pp, multiple formats

The History of Mathematical Symbols
by Douglas Weaver and Anthony D. Smith

A History of Mathematics
by Florian Cajori, 1909, 556 pages, PDF/TeX

History of Modern Mathematics
by David Eugene Smith, 1906, 75 pages, PDF/TeX

A History Of The Mathematical Theory Of Probability
by I. Todhunter, 2007, 640 pages, 47MB, PDF

A History of the Progress of the Calculus of Variations during the Nineteenth Century
by Isaac Todhunter, 2005, 549 pages, 24MB, PDF

How to Read Mathematics
by Shai Simonson and Fernando Gouvea

Indian Mathematics
by G. R. Kaye, 1915, 102 pp, multiple formats

An Introduction to Mathematics
by A. N. Whitehead, 1911

Lectures on the History of Mathematics
by G. Donald Allen, Texas A&M University, 2003

The Manual of Mathematical Magic
by Peter McOwan, 2010, 96 pp, 8.9MB, PDF

The Mathemagician and Pied Puzzler: A Collection in Tribute to Martin Gardner
edited by Elwyn Berlekamp, Tom Rodgers, 1999, 251 pages, 2.3MB, PDF

Mathematical Discovery
by A.M. Bruckner, B.S. Thomson, J.B. Bruckner, 2011, 267 pp, 5.8MB, PDF

Mathematical Essays and Recreations
by Hermann Schubert, 1898, 159 pages, 1.1MB, PDF

Mathematical Measures, Mathematical Pleasures, Mathematical Treasures
by Stephen Clark, 2008, 48 pages, 5.1MB, PDF

Mathematical Omnibus: Thirty Lectures on Classic Mathematics
by Dmitry Fuchs, Sergei Tabachnikov, 2007, 465 pages, 11MB, PDF

Mathematical Recreations and Essays
by W. W. Rouse Ball, 1914, 506 pages, PDF/TXT/DJVU

Mathematics at the Edge of the Rational Universe
by Christopher Cooper, 2008, 115 pages, PDF

The Mathematics in Toys and Games
by Jing Li, Erik Demaine, Melissa Gymrek, 2010, PDF

Men of Mathematics
by E. T. Bell, 1937

The Millennium Prize Problems
edited by J. Carlson, A. Jaffe, A. Wiles, 2006, 139 pages, 1.1MB, PDF

Recreations in Mathematics
by H E. Licks, 1917, 163 pages, 9.2MB, PDF

A Short Account of the History of Mathematics
by W. W. Rouse Ball, 1960, 466 pages, 2.7MB, PDF

A Short History of Greek Mathematics
by James Gow, 1884, 351 pp, multiple formats

The Story of Euclid
by W. B. Frankland, 1902, 183 pages, 10MB, PDF

Ten British Mathematicians
by Alexander Macfarlane, 1916, 108 pages, PDF/TeX

Tertium Organum
by P.D. Ouspensky, 1920, 382 pages, 21MB, PDF

The Unknowable
by Gregory J. Chaitin, 1999, 122 pages, 600KB, PDF

Vedic Mathematics
by W. B. V. Kandasamy, F. Smarandache, 2006, 220 pages, 790KB, PDF