Left: The large rectangle is plastic and can be split into a square (blue) and two plastic rectangles (red and {green).
Centre: The two arcs drawn in each square.
Right: A Harriss spiral.
Image: Chalkdust.
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Headscratchers
We review the eighth of this year's nominees for Book of the Year
A canal runs through it
Colin Beveridge barges in and admires some curious railway bridges
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A crossnumber clue takes us plunging headfirst towards projective geometry
Killing by numbers: the mathematics of warfare
A blast from the past. Modelling battle grounds from ancient Greece.
Puzzles, Issue 02
These puzzles appeared in Issue 02 of the magazine.
Crossnumber winners
Are you a winner?