Here’s a puzzle a co-worker shared with me recently. See how you do with it!

Suppose you have five bags of gold coins. All of the coins weigh exactly 1 lb each except for all of the coins in one bag whose coins weigh 1 lb 1 oz each. The bags are unmarked, and there is no visible indication as to which bag holds which coins. The bags may contain different quantities of coins.

Suppose you have a scale on which you can make exactly one instantaneous measurement – put something on the scale, push the “Weigh” button, and you get a reading of the weight at the moment the button is pushed.

Using the scale, is it possible to identify which of the 5 bags contains the heavier coins with only a single measurement? If so, how?

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“A cleverly crafted puzzle is a work of intellectual art when the simplicity of its solution is beautifully hidden by the complexity of its design. Such art requires imagination and creativity on the part of the creator and requires the solver to walk the fine line between inspiration and insanity.”

Brian Smith, Author/Creator of the Cerebral Codex

Part novel, part puzzle, part quest … it is difficult to find a single description that adequately describes the Cerebral Codex.

The Novel

The story begins with the protagonists Bret and Jon fighting for their very survival swimming through a rough sea in a raging storm. Sighting an island in the distance, they manage to avoid drowning and swim to the safety of the shore. After recovering on the island, they discover hidden deep within an old stone library the Cerebral Codex, which told a unique and intriguing tale.

In this mysterious environment, the two friends find themselves in a strange place with only the Cerebral Codex to help guide them. They find that the Codex is riddled with mind bending and mysterious mental challenges, which when solved lead them on an adventure like no other.

The Puzzle

As the characters in the novel encounter puzzles, you are given similar challenges to solve. Work to solve the puzzles and uncover hidden information in the codex and begin your own adventure.  This is a multi-stage challenge which has several levels each consisting of a mental challenge (puzzle) followed by a physical challenge.  Can you unlock the mysteries encoded deep within the Cerebral Codex?

The Quest

There are two ways to claim credit for solving the Cerebral Codex. As a cache finder or as a distance solver.

If you choose to find the cache in person, you’ve got quite a trek ahead of you. The Cerebral Codex geocache is set in the heart of the Wharton State Forest in New Jersey, USA. With over 100,000 acres, Wharton is the largest New Jersey State Forest and provides a great backdrop for this challenge.  While the cache itself is located in Wharton State Forest, this adventure will take you well beyond it’s boundaries in search of the puzzle pieces that you need to access the final cache container, the logbook, and the Codex Bonus Cache Travel Bug.

If you decide to tackle this as a distance solver, you’ve got a different sort of trek ahead of you. Download the novel, and read the entire thing. Solve the first ten puzzles to unlock the twenty Meshulash pieces. Use the Meshulash pieces to solve the final puzzle.  When you solve the final puzzle, you’ll be given the tracking code for the Codex Distance Solver Travel Bug.

The Cerebral Codex  was not designed to be tackled in a weekend – it will take thought, time and (if you attempt to find the cache) several trips.

Getting Started

If you are ready to tackle the challenge of the Cerebral Codex, click on one of the following links:

Geocache Hunters: Visit the cache page for GCVJXQ
Distance Solvers: Download the novel and begin solving from home

Sudoku puzzles became an international phenomenon in 2005. But they have a long and storied history that – despite conventional wisdom – does not begin in Japan.

The concept of filling a square grid with unique symbols (called a Latin square or magic square) has existed for hundreds of years. The first 9×9 number puzzles began appearing in French newspapers in 1892 (as in the example image below). These puzzles required unique numbers 1-9 in each row and column and inner 3×3 subsquare as well as long the long diagonals. These puzzles all but disappeared from print by the time World War I began.

The modern Sudoku was most likely designed anonymously by Howard Garns, a 74-year-old retired architect and freelance puzzle constructor from Indiana, and first published in 1979 by Dell Magazines as Number Place. He died in 1989 before getting a chance to see his creation as a worldwide phenomenon.

In 1984, Japanese game publisher Nikoli (which will be the subject of a future Puzzlehead article) picked up the idea of Number Place and ran with it. The publisher made two small changes to the concept and renamed it “su-doku”, meaning “single number”. The game became an overnight sensation in newspapers in Japan, possibly because the Japanese language is ill-suited to use in crossword puzzles.

In 1997, New Zealander Wayne Gould was shopping in Tokyo when he picked up a book of sudoku and was instantly hooked. Gould developed a computer program to automatically crank out sudoku puzzles and began selling them on his web site www.sudoku.com. In 2004, he published one of his puzzles in a newspaper in Conway, New Hampshire, and later that year The Times in Britain launched sudoku as a regular feature.

Today, there are many, many variants of sudoku, ranging from different dimensions (such as 2×3 rectangles in a 6×6 grid to 16×16 grids with 4×4 subsquares), oddly-shaped subcells, overlapping puzzles of different sizes, and more. Sudoku has appeared on virtually every medium available, even TV and radio. It has even spawned an annual worldwide competition for die-hard solvers.

Sudoku can be terribly addictive. In Australia in June 2008, a mistrial was declared in a drugs-related jury trial when it was discovered that five of the twelve jurors had been playing Sudoku instead of listening to evidence.

So, what is sudoku, really? The 2 Hot Girls in the Shower have an answer for you. (Don’t worry – despite the name, the link is family friendly.)